[CMake] [darwin] [builtins] Should install the lipo'd builtin libraries.
[CMake] [darwin] [builtins] Should install the lipo'd builtin libraries.

On darwin we don't install the single-architecture builtin libraries, but we do need to install the lipo'd ones.

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@248630 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt