[CMake] Move LLVMBUILD_LIB_DEPS stuff from add_llvm_library (and LLVm-Config) to llvm_add_library to centralize target_link_libraries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202260 91177308-0d34-0410-b5e6-96231b3b80d8
[CMake] Work around to use target_link_libraries(PUBLIC) in BUILD_SHARED_LIBS mode.

FIXME: It may be PRIVATE since SO knows its dependent libs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202261 91177308-0d34-0410-b5e6-96231b3b80d8