Issue building on M1 Mac

[NetOpWibby]

I want to try porting the Ledger Handshake app to my Stax. I'm not a Rust dev so I'm really just trying to see what I can figure out. Anyhoo, here's some errors!

---

backtrace

error: could not compile `app-boilerplate-rust` (bin "app-boilerplate-rust") due to 2 previous errors
thread 'main' panicked at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/cargo-ledger-1.5.1/src/main.rs:274:41:
called `Option::unwrap()` on a `None` value
stack backtrace:
   0: rust_begin_unwind
             at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:645:5
   1: core::panicking::panic_fmt
             at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/panicking.rs:72:14
   2: core::panicking::panic
             at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/panicking.rs:127:5
   3: cargo_ledger::build_app
   4: cargo_ledger::main
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

verbose backtrace

error: could not compile `app-boilerplate-rust` (bin "app-boilerplate-rust") due to 2 previous errors
thread 'main' panicked at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/cargo-ledger-1.5.1/src/main.rs:274:41:
called `Option::unwrap()` on a `None` value
stack backtrace:
   0:        0x1049ed880 - std::backtrace_rs::backtrace::libunwind::trace::h71068c4b5b031286
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:        0x1049ed880 - std::backtrace_rs::backtrace::trace_unsynchronized::h56b9813f75d4d961
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:        0x1049ed880 - std::sys_common::backtrace::_print_fmt::hb10f64f159882954
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/sys_common/backtrace.rs:67:5
   3:        0x1049ed880 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h052d4a6449303d0c
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/sys_common/backtrace.rs:44:22
   4:        0x104a08f54 - core::fmt::rt::Argument::fmt::h670e0fc9dd75299f
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/fmt/rt.rs:142:9
   5:        0x104a08f54 - core::fmt::write::hd7376fa11f842969
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/fmt/mod.rs:1117:17
   6:        0x1049eb464 - std::io::Write::write_fmt::h8962cd07816e935b
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/io/mod.rs:1762:15
   7:        0x1049ed6bc - std::sys_common::backtrace::_print::h40815699fd9e306f
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/sys_common/backtrace.rs:47:5
   8:        0x1049ed6bc - std::sys_common::backtrace::print::h97fb0a8a4077c481
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/sys_common/backtrace.rs:34:9
   9:        0x1049eeadc - std::panicking::default_hook::{{closure}}::h3b4672ac61ca5355
  10:        0x1049ee824 - std::panicking::default_hook::h609e6a125a90b4e7
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:292:9
  11:        0x1049eef04 - std::panicking::rust_panic_with_hook::h9625542414b348eb
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:779:13
  12:        0x1049eede0 - std::panicking::begin_panic_handler::{{closure}}::hb4fa343c314105dc
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:649:13
  13:        0x1049edce8 - std::sys_common::backtrace::__rust_end_short_backtrace::he263cec7b035e782
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/sys_common/backtrace.rs:170:18
  14:        0x1049eeba0 - rust_begin_unwind
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:645:5
  15:        0x104a13e54 - core::panicking::panic_fmt::h624e311b541e9a0d
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/panicking.rs:72:14
  16:        0x104a13ec8 - core::panicking::panic::hd40edd9c8c526f5b
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/panicking.rs:127:5
  17:        0x10493d9c4 - cargo_ledger::build_app::hc0f170576384f444
  18:        0x10493ad0c - cargo_ledger::main::h2d02167acf61d2a7
  19:        0x104958be4 - std::sys_common::backtrace::__rust_begin_short_backtrace::ha1b641d4a7d80261
  20:        0x104959bec - std::rt::lang_start::{{closure}}::h03b4535688bd23ea
  21:        0x1049e6d10 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h07136ef239371295
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/core/src/ops/function.rs:284:13
  22:        0x1049e6d10 - std::panicking::try::do_call::hc67f66b8c648ad32
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:552:40
  23:        0x1049e6d10 - std::panicking::try::hf97491b0e67985d1
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:516:19
  24:        0x1049e6d10 - std::panic::catch_unwind::h29050b1d23639a61
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panic.rs:142:14
  25:        0x1049e6d10 - std::rt::lang_start_internal::{{closure}}::hcead3afc42fd36ce
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/rt.rs:148:48
  26:        0x1049e6d10 - std::panicking::try::do_call::hc86b0a533f7b067b
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:552:40
  27:        0x1049e6d10 - std::panicking::try::hb1cdabe993a5546d
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panicking.rs:516:19
  28:        0x1049e6d10 - std::panic::catch_unwind::h21666380498b6e46
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/panic.rs:142:14
  29:        0x1049e6d10 - std::rt::lang_start_internal::h7be4efcec2e53815
                               at /rustc/0f44eb32f1123ac93ab404d74c295263ce468343/library/std/src/rt.rs:148:20
  30:        0x104959bd0 - std::rt::lang_start::h067369dbda6b583d
  31:        0x10494008c - _main