(cie_compare): Removed.
(cie_eq, cie_hash, cie_compute_hash): New functions.
(_bfd_elf_discard_section_eh_frame): Rewrite not to rely on FDEs
pointing only to last CIE and allow merging of any duplicate CIEs,
not just duplicate consecutive CIEs.
(_bfd_elf_discard_section_eh_frame_hdr): Delete cies hash table.
* elf-bfd.h (struct cie_header, struct cie): Removed.
(struct eh_frame_sec_info): Remove alloced field.
(struct eh_frame_hdr_info): Remove last_cie, last_cie_sec
and last_cie_inf fields. Add cies field.
* ld-elf/eh5.d: New test.
* ld-elf/eh5.s: New file.
* ld-elf/eh5a.s: New file.
* ld-elf/eh5b.s: New file.
