Re-enable verification of test and update outdated diag checks

Going by PR6913 it looks like this one can no longer reach CodeGen so remove
the redundant -emit-llvm case and treat it as an ordinary Sema test.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196736 91177308-0d34-0410-b5e6-96231b3b80d8