storage: Allow both "readonly" and "read-only" spelling in crypttab

The man page mentions both, so let's not get confused when someone
uses "read-only".

pkg/storaged/utils.js

@@ -102,6 +102,7 @@ export function set_crypto_options(block, readonly, auto, nofail, netdev) {
         const opts = config.options ? parse_options(decode_filename(config.options.v)) : [];
         if (readonly !== null) {
             extract_option(opts, "readonly");
+            extract_option(opts, "read-only");
             if (readonly)
                 opts.push("readonly");
         }