HPPA64 linker segmentation faults

HPPA64 linker segmentation faults

One of the ld tests produces:
failed with: <Segmentation fault>, no expected output
FAIL: Discarded dynamic relocation section

This patch cures the segv.  (The test still fails with ld producing
a really messed up output, DT_RELA at address 0!)

	PR 24596
	* elf64-hppa.c (elf64_hppa_finalize_dynreloc): Get the output bfd
	from bfd_link_info, not an output section owner.
	(elf64_hppa_finish_dynamic_symbol, elf64_hppa_finalize_opd): Likewise.
	(elf_hppa_final_link_relocate): Likewise.