* config/tc-mips.c (set_at): Added unsignedp argument. Use

	* config/tc-mips.c (set_at): Added unsignedp argument.  Use
	load_register.
	(set_at_unsigned): Removed; changed callers to use set_at.
	(load_register): Removed unused ip argument.  Changed callers.
	(append_insn): Don't swap branch and branch likely.
	(macro_build): Handle 'u'.
	(load_register): Handle 64 bit constants.
	(macro): Added M_DABS, removed M_ABSU.  Numerous changes to
	support 64 bit constants.
	(mips_ip): Use hex constants in range checks for clarity.
	(md_number_to_chars): Support 8 byte values.