* Rename existing relocations to be more specific

* Add relocations for refernces to non-lazy darwin stubs and implement
  them correctly.

With this change, we can correctly references external globals, and now
all but two UnitTests and all but 1 Regression/C tests pass.

More importantly, bugpoint-jit will start giving us useful testcases,
instead of always telling us that references to external globals don't
work :)

llvm-svn: 18222