Change type of XOP flag in code emitters to a bool. Remove a some unneeded cases from switch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191632 91177308-0d34-0410-b5e6-96231b3b80d8
Revert accidental commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191633 91177308-0d34-0410-b5e6-96231b3b80d8