Avoid multiple definition warnings when both config.h and
llvm-config.h are included.

This is the cmake counterpart of r110547. See bug #7809.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110753 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed