bin/69268: Fix ndiscvt to warn you if it's going to generate a useless module

[Daniel O'Connor]

>Number:         69268
>Category:       bin
>Synopsis:       Fix ndiscvt to warn you if it's going to generate a useless module
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 19 08:00:49 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Daniel O'Connor
>Release:        FreeBSD 5.2-CURRENT i386
>Organization:
>Environment:
System: FreeBSD inchoate.localdomain 5.2-CURRENT FreeBSD 5.2-CURRENT #1: Wed Jul 7 06:18:08 CST 2004 darius at inchoate.dons.net.au:/usr/obj/usr/src/sys/INCHOATE i386

>Description:
Some drivers (eg Intel Wireless 2100) for Windows 2000 cause ndiscvt to generate a driver which doesn't match any hardware. This patch causes it to generate a error in this case.

>How-To-Repeat:
Use the NDIS5 Intel Wireless 2100 drivers with ndiscvt and try and load the resulting kld - it doesn't attach to anything.
>Fix:
http://www.gsoft.com.au/~doconnor/ndiscvt-warnonempty.diff

>Release-Note:
>Audit-Trail:
>Unformatted: