INT 2F U - DRIVER.SYS support - ADD NEW BLOCK DEVICE                            
	AX = 0801h
	DS:DI -> drive data table (see #02601,#02602,#02603)
Return: AX,BX,SI,ES destroyed
Notes:	moves down internal list of drive data tables, copying and modifying
	  the drive description flags word for tables referencing same physical
	the data table is appended to the chain of tables
	supported by DR DOS 5.0 and Novell DOS 7
SeeAlso: AX=0803h