Remove special form of AddRegFrm used by FP instructions. These instructions can be handled by MRMXr instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198238 91177308-0d34-0410-b5e6-96231b3b80d8
Merge case statements to remove redundant code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198241 91177308-0d34-0410-b5e6-96231b3b80d8