R600: Clean up comments in Processors.td

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181032 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Add pattern for SHA-256 Ma function

This can be optimized using the BFI_INT instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181033 91177308-0d34-0410-b5e6-96231b3b80d8
R600: BFI_INT is a vector-only instruction

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181034 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Expand vector or, shl, srl, and xor nodes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181035 91177308-0d34-0410-b5e6-96231b3b80d8