May unlock features that are not exposed by march.

Change-Id: I4f10dfc93f75eab502824ec155daa9fbbb3d3d55
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/33773Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>