When building with LTO, builtin functions that are defined but whose calls have not been inserted yet, get internalized.
We need to prevent these symbols from being internalized at LTO time.
Refer to https://reviews.llvm.org/D49434.
apparently I missed some tests in the last commit. Rather than having
dozens of tests use the long version, use the short version in
`run-make` and the long version in `run-make-fulldeps` (which is now
only three tests)
