Add support for mips16 (16 bit MIPS implementation):

	Add support for mips16 (16 bit MIPS implementation):
	* gencode.c (inst_type): Add mips16 instruction encoding types.
	(GETDATASIZEINSN): Define.
	(MIPS_DECODE): Add REG flag to dsllv, dsrav, and dsrlv.  Add
	jalx.  Add LEFT flag to mfhi and mflo.  Add RIGHT flag to mthi and
	mtlo.
	(MIPS16_DECODE): New table, for mips16 instructions.
	(bitmap_val): New static function.
	(struct mips16_op): Define.
	(mips16_op_table): New table, for mips16 operands.
	(build_mips16_operands): New static function.
	(process_instructions): If PC is odd, decode a mips16
	instruction.  Break out instruction handling into new
	build_instruction function.
	(build_instruction): New static function, broken out of
	process_instructions.  Check modifiers rather than flags for SHIFT
	bit count and m[ft]{hi,lo} direction.
	(usage): Pass program name to fprintf.
	(main): Remove unused variable this_option_optind.  Change
	``*loptarg++'' to ``loptarg++''.
	(my_strtoul): Parenthesize && within ||.
	* interp.c (sim_trace): If tracefh is NULL, set it to stderr.
	(LoadMemory): Accept a halfword pAddr if vAddr is odd.
	(simulate): If PC is odd, fetch a 16 bit instruction, and
	increment PC by 2 rather than 4.
	* configure.in: Add case for mips16*-*-*.
	* configure: Rebuild.