Shared compilation with iOS target is broken

[yaroslavyaroslav]

Details

When running tests in cargo test --target aarch64-apple-ios configuration the test that is required shaders to run fails with the error below:

     Running unittests src/lib.rs (target/aarch64-apple-ios/debug/deps/mopro_msm-b350a09449b0df83)
error: test failed, to rerun pass `--lib`

Caused by:
  process didn't exit successfully: `gpu-acceleration/target/aarch64-apple-ios/debug/deps/mopro_msm-b350a09449b0df83 test_barrett_reduce_with_mont_params` (signal: 9, SIGKILL: kill)

Seems that this happens due to a bug within shader.rs::compile_metal function to be discovered and fixed.

Acceptance criteria

Successfully running tests with iOS target