This test includes stdint.h, which might include system headers (and that might
not work, depending on the system configuration). Attempting to fix
llvm-clang-lld-x86_64-debian-fast.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@218959 91177308-0d34-0410-b5e6-96231b3b80d8