Replace mandatory_prefix with prefix_requirement

Replace mandatory_prefix with prefix_requirement

	* i386-dis.c (PREFIX_MANDATORY_REPZ): Removed.
	(PREFIX_MANDATORY_REPNZ): Likewise.
	(PREFIX_MANDATORY_DATA): Likewise.
	(PREFIX_MANDATORY_ADDR): Likewise.
	(PREFIX_MANDATORY_LOCK): Likewise.
	(PREFIX_MANDATORY): Likewise.
	(PREFIX_UD_SHIFT): Set to 8
	(PREFIX_UD_REPZ): Updated.
	(PREFIX_UD_REPNZ): Likewise.
	(PREFIX_UD_DATA): Likewise.
	(PREFIX_UD_ADDR): Likewise.
	(PREFIX_UD_LOCK): Likewise.
	(PREFIX_IGNORED_SHIFT): New.
	(PREFIX_IGNORED_REPZ): Likewise.
	(PREFIX_IGNORED_REPNZ): Likewise.
	(PREFIX_IGNORED_DATA): Likewise.
	(PREFIX_IGNORED_ADDR): Likewise.
	(PREFIX_IGNORED_LOCK): Likewise.
	(PREFIX_OPCODE): Likewise.
	(PREFIX_IGNORED): Likewise.
	(Bad_Opcode): Replace PREFIX_MANDATORY with 0.
	(dis386_twobyte): Replace PREFIX_MANDATORY with PREFIX_OPCODE.
	(three_byte_table): Likewise.
	(mod_table): Likewise.
	(mandatory_prefix): Renamed to ...
	(prefix_requirement): This.
	(prefix_table): Replace PREFIX_MANDATORY with PREFIX_OPCODE.
	Update PREFIX_90 entry.
	(get_valid_dis386): Check prefix_requirement to see if a prefix
	should be ignored.
	(print_insn): Replace mandatory_prefix with prefix_requirement.