Mac OS X CMake fix: generate LLDB version from xcodeproj
- This resolves the remaining issues related to building lldb utility/dylib
- TODO: fix up debugserver build

Patch by Ahmed Bougacha!



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@182751 91177308-0d34-0410-b5e6-96231b3b80d8