[AArch64] Set FMOVS0 and FMOVD0 as isAsCheapAsAMove when needed.

If a subtarget has both ZCZeroing and CustomCheapAsMoveHandling features (now
only Kryo has both), set FMOVS0 and FMOVD0 isAsCheapAsAMove.

Differential Revision: http://reviews.llvm.org/D22256

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275178 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed