Fix a few more grammatic errors in docs/TableGen/index.rst


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204364 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-profdata: Remove an empty comment

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204370 91177308-0d34-0410-b5e6-96231b3b80d8