more on if_sk problem

I have done some more twiddling around with the problem I'm having with the
if_sk driver with a built-in 3com 940 Gig-e adapter.

Basically the problem is that dhclient times out and I end up with an address of
0.0.0.0 when I boot the machine. I've found that if I remove IFF_MULTICAST from
line 1473 of that driver, recompile the kernel, and reboot, dhcp suddenly works
right.

Another thing I noticed is that every time an IP is added to the interface with
multicast enabled, the link goes down, and typing a subsequent ifconfig shows
"No carrier" for a few seconds. I don't see this behavior on any other ethernet
card (I have several fxp, xl, and de type 10/100 cards). So basically I think
there's some kind of problem with the sk_setmulti() function in the sk driver.
Either that or the 3com 940 card is just wonky.

Anyway, this is what I've found, so hopefully someone can do something with this
info.

Ken