Teach TableGen to understand X.Y notation in the TSFlagsFields strings.

Remove much horribleness from X86InstrFormats as a result. Similar
simplifications are probably possible for other targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99539 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed