RET/RETF - Return From Procedure

	Usage:	RET	nBytes
		RETF	nBytes
		RETN	nBytes
	Modifies flags: None

	Transfers control from a procedure back to the instruction address
	saved on the stack.  "n bytes" is an optional number of bytes to
	release.  Far returns pop the IP followed by the CS, while near
	returns pop only the IP register.

				 Clocks			Size
	Operands	 808x  286    386   486		Bytes

	retn		16/20  11+m  10+m    5		  1
	retn immed	20/24  11+m  10+m    5		  3
	retf		26/34  15+m  18+m    13		  1
	retf (PM, same priv.)	-    32+m    18		  1
	retf (PM, lesser priv.)	-      68    33		  1
      	retf immed	25/33  15+m  18+m    14		  3
	retf immed (PM, same priv.)  32+m    17		  1
	retf immed (PM, lesser priv.)  68    33		  1


	- see Instruction Timing