INT 2F - DOS 3.3+ KEYB.COM - SET KEYBOARD MAPPING

	AX = AD82h
	BL = new state
	    00h US keyboard (Control-Alt-F1)
	    FFh foreign keyboard (Control-Alt-F2)
Return: CF set on error (BL not 00h or FFh)
	CF clear if successful
Notes:	this function was undocumented prior to the release of DOS 5.0
	the states 00h and FFh correspond with the byte stored at offset +02h
	  in KEYBs INT 09h handler
SeeAlso: AX=AD80h,AX=AD81h,AX=AD83h,AX=AD84h