X86: specify CPU on new test to fix atom buildbot

Apparently Atoms use lea for stack adjustment, which we weren't
looking for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187704 91177308-0d34-0410-b5e6-96231b3b80d8
AVX-512 set: added VEXTRACTPS instruction

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187705 91177308-0d34-0410-b5e6-96231b3b80d8