* i386-tdep.h (i386_abi): New enum.

* i386-tdep.h (i386_abi): New enum.
(struct gdbarch_tdep): Replace os_ident member with abi.
(i386_gdbarch_register_os_abi): New prototype.
* i386-tdep.c (i386_abi_names): New array.
(process_note_abi_tag_sections): Removed.
(process_note_sections): New function.
(i386_elf_abi_from_note, i386_elf_abi): New functions.
(struct i386_abi_handler): New struct.
(i386_abi_handler_list): New variable.
(i386_gdbarch_register_os_abi): New function.
(i386_gdbarch_init): Adapt for the changes given above.