UseListOrder: Remove move assignment

Remove the move assignment added in r214213, since it wasn't necessary
to fix the bots (r214224 was the magic touch).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214260 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed