Transforms: Try harder to fix bootstrap after r266565

This catches two nullptr insertions into the ValueMap I missed in
r266567.  I missed CloneFunction becuase it never calls RemapInstruction
directly.  Here's one of the still-failing bots:
  http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/11496

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266570 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed