INT 21 - Novell NetWare - WORKSTATION - GET PREFERRED CONNECTION ID             
	AX = F001h
Return: AL = connection ID of preferred file server (1-8), 00h if not set
Notes:	this function is supported by Advanced NetWare 1.0+
	the preferred connection ID is set to 00h by the shell on EOJ
SeeAlso: AH=D6h,AX=EF03h,AX=F000h,AX=F002h,AX=F005h