CMake: Add LLVM_INSTALL_TOOLCHAIN_ONLY option.

Differential Revision: http://llvm-reviews.chandlerc.com/D1428

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189155 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfoFinder: handle imported entities of a CU.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189158 91177308-0d34-0410-b5e6-96231b3b80d8