Revert "Add support for named values in the parser."
This was submitted before it was ready.

This reverts commit 62060a01e095cf35eb9ca42a333752d12714f35c.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@205533 91177308-0d34-0410-b5e6-96231b3b80d8