[CMake] Add llvm-ar subdirectory explicitly.

This is required because ExternalProject_Add requires all targets specified in the DEPENDS argument must exist before calling ExternalProject_Add.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247592 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed