[lldb] Include llvm-config.h instead of config.h

This distinction doesn't matter for an in-tree build, but when building
against an installed llvm, only the former is present.

This should fix the LLDB Standalone bot:
http://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake-standalone/

GitOrigin-RevId: 4d593efd7f930c42be8553a5ba347e2d87503ad4
1 file changed