INT 4D - TI Professional PC - DISK - GET RETRY STATUS OF LAST OPERATION

	AH = 07h
	DL = drive (bit 7 set for hard disk)
Return: CF clear if status unchanged
	CF set if status changed since last call
	AH = 00h
	AL = status of previous operation (see #00234 at INT 13/AH=01h)
Notes:	this function is nearly the same as INT 13/AH=01h on a standard PC BIOS
	the TI's BIOS tranparently performs a number of retries; this function
	  returns the error status of a failed operation even if the operation
	  succeeded on a retry
SeeAlso: AH=00h,AH=01h,INT 13/AH=01h