This test doesn't need -O2 -disable-llvm-optzns

I forgot to fix this one in r209145. We use these flags on dllimport tests
to make sure we emit code for available_externaly functions and don't inline
the IR.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209564 91177308-0d34-0410-b5e6-96231b3b80d8