There is no need to merge the globals graph into the function graphs at the

There is no need to merge the globals graph into the function graphs at the
end of the BU and CBU passes.  The globals will be marked incomplete, so it
doesn't matter if they are missing some info, and merging isn't guaranteed
to bring everything in anyway!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11684 91177308-0d34-0410-b5e6-96231b3b80d8