INT 2F - Novell DOS 7+ FDOS EXTENSIONS - FREE FAT CHAIN

	AX = 1004h
	BX = first block to release on current drive
Return: nothing
Notes:	This private function is called internally by the OS kernel to
	  ask the FDOS to release the FAT chain.  By using the INT 2F/AX=1001h
	  FDOS hook, the call can be intercepted by external system components
	  such as the DELWATCH TSR.
	This function must under no circumstances be called by applications!
SeeAlso: INT 2F/AX=1001h,AX=1005h,AX=10FEh