* Makefile.in (SFILES): Add osabi.c.

* Makefile.in (SFILES): Add osabi.c.
(COMMON_OBS): Add osabi.o.
(osabi.o): New dependency list.
* osabi.c: New file.
* osabi.h: New file.
* doc/gdbint.texinfo: Document new generic OS ABI framework.

* Makefile.in (alpha_tdep_h): Define and use instead of
alpha-tdep.h.
* alpha-tdep.c (alpha_abi_names, process_note_abi_tag_sections,
get_elfosabi, alpha_abi_handler_list, alpha_gdbarch_register_os_abi):
Remove.
(alpha_gdbarch_init, alpha_dump_tdep): Use generic OS ABI framework.
* alpha-tdep.h: Include osabi.h.
(alpha_abi): Remove.
(gdbarch_tdep): Use generic OS ABI framework.
* alpha-linux-tdep.c (_initialize_alpha_linux_tdep): Use
gdbarch_register_osabi.
* alpha-osf1-tdep.c (_initialize_alpha_osf1_tdep): Likewise.
* alphafbsd-tdep.c (_initialize_alphafbsd_tdep): Likewise.
* alphanbsd-tdep.c (_initialize_alphanbsd_tdep): Likewise.

* Makefile.in (sh_tdep_h): Add osabi.h.
* sh-tdep.h (sh_osabi): Remove.
(gdbarch_tdep): Use generic OS ABI framework.
* sh-tdep.c (sh_osabi_names, process_note_abi_tag_sections,
sh_osabi_handler_list, sh_gdbarch_register_os_abi): Remove.
(sh_gdbarch_init, sh_dump_tdep): Use generic OS ABI framework.
* shnbsd-tdep.c (_initialize_shnbsd_tdep): Use gdbarch_register_osabi.

* Makefile.in (arm_tdep_h): Define and use instead of arm-tdep.h.
* arm-linux-tdep.c (_initialize_arm_linux_tdep): Use
gdbarch_register_osabi.
* arm-tdep.c (arm_abi_names, process_note_abi_tag_sections,
arm_abi_handler_list, arm_gdbarch_register_os_abi): Remove.
(get_elfosabi): Rename to...
(arm_elf_osabi_sniffer): ...this.  Adjust to use generic OS
ABI framework support routines.
(arm_gdbarch_init): Use generic OS ABI framework.
(arm_dump_tdep): Likewise.
(_initialize_arm_tdep): Likewise.
* arm-tdep.h: Include osabi.h.
(arm_abi): Remove.
(gdbarch_tdep): Remove arm_abi and abi_name members.  Add
osabi member.
(arm_gdbarch_register_os_abi): Remove prototype.
* armnbsd-tdep.c (arm_netbsd_aout_osabi_sniffer): New function.
(_initialize_arm_netbsd_tdep): Use gdbarch_register_osabi.

* Makefile.in (mips-tdep.o): Add osabi.h to dependency list.
* mips-tdep.c: Include osabi.h.
(gdbarch_tdep, mips_gdbarch_init, mips_dump_tdep): Use generic
OS ABI framework.