SubtargetFeature.h is currently part of MC while it doesn't depend on
anything in MC. Since some LLVM components might have the need to work
with target features without necessarily needing MC, it might be
worthwhile to move SubtargetFeature.h to a different location. This will
reduce the dependencies of said components.
Note that I choose TargetParser as the destination because that's where
Triple lives and SubtargetFeatures feels related to that. Suggestions
for alternative locations are welcome.
This issues came up during a JITLink review (D149522). JITLink would
like to avoid a dependency on MC while still needing to store target
features.
I'm not entirely sure who should review this patch so please add more
reviewers if necessary.