Constify target name, reloc name, and carsym name

Constify target name, reloc name, and carsym name

bfd/
	* bfd-in.h (carsym.name): Make const.
	* reloc.c (struct reloc_howto_struct.name): Likewise.
	* targets.c (bfd_target.name): Likewise.!
	* bfd.c (bfd_get_sign_extend_vma): Make variable const.
	* som.c (som_bfd_fill_in_ar_symbols): Use an intermediary variable
	when setting carsym.name.
	* bfd-in2.h: Regenerate.
gdb/
	* amd64-dicos-tdep.c (amd64_dicos_osabi_sniffer): Constify target.
	* i386-cygwin-tdep.c (i386_cygwin_init_abi): Likewise.
	* i386-dicos-tdep.c (i386_dicos_osabi_sniffer): Likewise.
ld/
	* ldlang.c (stricpy, strcut, name_compare): Constify params.
	(get_first_input_target): Make return and "target" const.