LOOPNZ/LOOPNE - Loop While Not Zero / Loop While Not Equal

	Usage:	LOOPNZ	label
		LOOPNE	label
	Modifies flags: None

	Decrements CX by 1 (without modifying the flags) and transfers
	control to "label" if CX != 0 and the Zero Flag is clear.  The
	"label" operand must be within -128 or 127 bytes of the instruction
	following the loop instruction.


				 Clocks			Size
	Operands	 808x  286   386   486		Bytes

	label:	jump	  19   8+m  11+m    9		  2
		no jump	   5	4     ?	    6


	- see Instruction Timing