Comment cleanup. NFC.

Don't duplicate names in comments and remove useless ones. Hopefully anyone
reading this knows what main is.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220298 91177308-0d34-0410-b5e6-96231b3b80d8
Test commit
Fixing brief comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220299 91177308-0d34-0410-b5e6-96231b3b80d8
Silence a -Wcast-qual warning; NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220300 91177308-0d34-0410-b5e6-96231b3b80d8