INT 13 - IBM/MS INT 13 Extensions - GET DRIVE PARAMETERS

	AH = 48h
	DL = drive (80h-FFh)
	DS:SI -> buffer for drive parameters (see #00273)
Return: CF clear if successful
	    AH = 00h
	    DS:SI buffer filled
	CF set on error
	    AH = error code (see #00234)
BUGS:	several different Compaq BIOSes incorrectly report high-numbered
	  drives (such as 90h, B0h, D0h, and F0h) as present, giving them the
	  same geometry as drive 80h; as a workaround, scan through disk
	  numbers, stopping as soon as the number of valid drives encountered
	  equals the value in 0040h:0075h
	Dell machines using PhoenixBIOS 4.0 Release 6.0 fail to correctly
	  handle this function if the flag word at DS:[SI+2] is not 0000h
	  on entry
SeeAlso: AH=08h,AH=41h,AH=49h,MEM 0040h:0075h