* arch-utils.c (gdbarch_info_fill): Also try core_bfd.

	* arch-utils.c (gdbarch_info_fill): Also try core_bfd.
	* corelow.c (core_read_description): New.
	(init_core_ops): Set to_read_description.
	* gdbarch.sh: Add gdbarch_core_read_description.
	* mips-linux-tdep.c (mips_linux_core_read_description): New.
	(mips_linux_init_abi): Call set_gdbarch_core_read_description.
	* mips-tdep.c (mips_tdesc_gp32, mips_tdesc_gp64): New.
	(mips_register_g_packet_guesses): Use them.
	(_initialize_mips_tdep): Initialize them.
	* mips-tdep.h (mips_tdesc_gp32, mips_tdesc_gp64): Declare.
	* gdbarch.h, gdbarch.c: Regenerated.