IR: Fix type-refs in testcase from r266548

There's a hole in the verifier right now: if a module has no compile
units, it never checks that all the string-based DITypeRefs get
resolved.  As a result, this testcase didn't fail the verifier, even
there were references to `!"has-uuid"` instead of `!"uuid"` (the former
was a composite type's 'name:' field, the latter its 'identifier:'
field).

I'm currently working on removing string-based type refs entirely, and
this testcase started failing (because the upgrade script can't resolve
the type refs).  Rather than fixing the (about-to-be-removed) hole in
the verifier, I'm just going to fix the test so that my upgrade script
handles it.

llvm-svn: 266553