[PATCH] sky2: remove support for untested Yukon EC/rev 0

The Yukon EC/rev0 (A1) chipset requires a bunch of workarounds. I copied these
from sk98lin.  But since they never got tested and add more cruft to the code;
any attempt at using driver as is on this version will probably fail.

It looks like this was a early engineering sample chip revision, if it ever shows
up on a real system. Produce an error message.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>