This replaces the hard coded path.
This looks fine.
There is no xcode build. If you want to test building the framework, you just need to set LLDB_BUILD_FRAMEWORK cmake variable. I don't know if there's any other var than needs setting, but we have a cache file (cmake/caches/Apple-lldb-Xcode.cmake), which should build things the same way as the apple folks are building, so you could just use that.
I guess this is unused now.