When +RTS -xp is passed, when don't need the X86_64_ELF_NONPIC_HACK,
becasue the relocation offset should only be out of range if
- the object file was not compiled with -fPIC -fexternal-dynamic-refs;
- ghc generates non-pic code while it should (e.g. Trac #15723)
In either case, we should print an error message rather that silently
attempt to use a hacky workaround that may not work.