[TableGen] Remove what seems to be an unnecessary std::map copy.

The comment says the copy was made so it could be destroyed in the following loop, but the original map wasn't used after the loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@337120 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed