[AVX-512] Pre-emptively fix more places in fastisel where we might copy a VK1 register into a AH/BH/CH/DH register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297704 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed