x86: Rename NumBytesForCalleeToPush to ...Pop for accuracy

If we have a callee cleanup convention, the callee is going to pop the
arguments off the stack, not push them on.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200566 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: Flag type unit references as declarations

This ensures DWARF consumers don't confuse these references for
definitions. I'd argue it might be nice to improve debuggers so we don't
need this, but it's just one field in an abbreviation anyway - so it
doesn't seem worth the fight.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200569 91177308-0d34-0410-b5e6-96231b3b80d8