* mips-tdep.c: Remove code which sets saved_regs from

	* mips-tdep.c: Remove code which sets saved_regs from
	init_extra_frame_info and put it in new function mips_find_saved_regs.
	(READ_FRAME_REG): Remove macro and replace uses with the expansion.
	* mips-tdep.c, config/mips/tm-mips.h: When examining ->saved_regs,
	check if it is NULL and call mips_find_saved_regs if so.