CMakeLists: Make variable shadowing a compile-time error

Now that the entire project is free of variable shadowing, we can enforce this as a compile time error to prevent any further introduction of this logic bug.

src/audio_core/CMakeLists.txt

@@ -49,9 +49,7 @@ if (NOT MSVC)
     target_compile_options(audio_core PRIVATE
         -Werror=conversion
         -Werror=ignored-qualifiers
-        -Werror=shadow
         -Werror=unused-parameter
-        -Werror=unused-variable
 
         $<$<CXX_COMPILER_ID:GNU>:-Werror=unused-but-set-parameter>
         $<$<CXX_COMPILER_ID:GNU>:-Werror=unused-but-set-variable>