[modules] Don't clobber a destructor's operator delete when adding another one;

move the operator delete updating into a separate update record so we can cope
with updating another module's destructor's operator delete.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@231735 91177308-0d34-0410-b5e6-96231b3b80d8