Fix layering of CodeGen/TargetOpcodes.def by moving it to Support

It's also used by utils/TableGen so needs to reside somewhere common to
TableGen and CodeGen.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328396 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed