* ld-elf/eh-frame-hdr.d: Replace target and xfail statements by single
`target: cfi'.
* ld-elf/eh-group.exp: Call check_as_cfi instead of is_elf_format.
* ld-elf/eh-group1.s, elf/eh-group2.s: Use more compatible section
flags prefix '%'.
* ld-elf/eh5.d: Replace target statement by `target: cfi' with an Alpha
exception. Relax the `Code alignment factor' matching.
* lib/ld-lib.exp: Rename istarget as istarget_ld.
(istarget, check_as_cfi): New procedure.
(run_dump_test): New comment for the virtual target `cfi'.
(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.
