Refactor C++ ops implementations (#603)

Author: scotts

src/torchcodec/decoders/_core/CMakeLists.txt

@@ -92,7 +92,7 @@ function(make_torchcodec_libraries
     set(custom_ops_library_name "libtorchcodec_custom_ops${ffmpeg_major_version}")
     set(custom_ops_sources
         AVIOBytesContext.cpp
-        VideoDecoderOps.cpp
+        custom_ops.cpp
     )
     set(custom_ops_dependencies
         ${decoder_library_name}
@@ -109,7 +109,7 @@ function(make_torchcodec_libraries
     set(pybind_ops_library_name "libtorchcodec_pybind_ops${ffmpeg_major_version}")
     set(pybind_ops_sources
         AVIOFileLikeContext.cpp
-        PyBindOps.cpp
+        pybind_ops.cpp
     )
     set(pybind_ops_dependencies
        ${decoder_library_name}