* elf64-alpha.c (ALPHA_ELF_LINK_HASH_PLT_LOC): New.
(struct alpha_elf_link_hash_entry): Add plt_old_section, plt_old_value.
(elf64_alpha_adjust_dynamic_symbol): Set them.
(elf64_alpha_size_plt_section_1): Reset them when plt entry removed.
(elf64_alpha_relax_tls_get_addr): Handle LDM relocs. Frob the
symbol index when relaxing LDM to TPREL.
(elf64_alpha_relax_section): Likewise. Allow relaxation of GD
relocs, even if the target isn't locally defined.
(elf64_alpha_check_relocs): Frob LDM reloc symndx to zero.
(elf64_alpha_relocate_section): Likewise. Force TP-relative
relocs vs symndx 0 to the tp base.