[CMake][Standalone] Fixup r197395 for standalone build.

Standalone scripts shall be rewritten.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197459 91177308-0d34-0410-b5e6-96231b3b80d8
[CMake][Standalone] Fix llvm-tblgen's directory to use LLVM_TOOLS_BINARY_DIR instead of LLVM_BINARY_DIR.

LLVM_BINARY_DIR points OBJROOT.

FIXME: llvm-config should show *real* bindir with --bindir.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197460 91177308-0d34-0410-b5e6-96231b3b80d8
[CMake][Standalone] Import LLVM_LIT_TOOLS_DIR.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197461 91177308-0d34-0410-b5e6-96231b3b80d8