docs: address post-commit review

Rewording/expansion of CMake options
suggested by Dan Liew.

See http://reviews.llvm.org/D16208.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258112 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed