Factor the loop for linking input files together into a combined module
into a separate function. This is in preparation for an upcoming patch
that runs the logic twice.
Patch by Luqman Aden!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235472 91177308-0d34-0410-b5e6-96231b3b80d8