[CMake] Add support for populating LLVM_REPOSITORY from CMake.

Autoconf does this in the GetRepositoryPath script, CMake's VersionFromVCS does grab the SVN_REVISION, but doesn't populate the repository URL.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257826 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed