Sink most of DwarfDebug::constructAbstractSubprogramScopeDIE down into DwarfCompileUnit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219476 91177308-0d34-0410-b5e6-96231b3b80d8
Sink the per-CU part of DwarfDebug::finishSubprogramDefinitions into DwarfCompileUnit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219477 91177308-0d34-0410-b5e6-96231b3b80d8