Add support for AVX registers to clang inline asm. Add a small testcase
and update the Sema testcase with a register that we won't hit for a while
I hope.

Fixes rdar://10510405

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@145671 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed