[PATCH] fix media detection for nForce 2 nics

[PATCH] fix media detection for nForce 2 nics

attached is a patch that polls the media setting for non GigE nForce
nics:
Without polling, media changes are not autodetected. This is fatal,
because the nic initialization is asynchroneous, thus "modprobe;ifup"
resulted in a dead network connection. The attached patch fixes that
problem.

It's a repost of a patch I sent around three weeks ago: you objected
that I rely on the nic irq instead of a software timer. I've documented
why this is ok.