[PATCH] sky2: beter ram buffer partitioning

Different chips have different sizes of ram buffers, and some versions have
no ram buffer at all!.  Be more careful about sizing the ram usage because
it maybe a problem if vendor keeps changing sizes.

There is the (unlikely) possibility that some of the errors on some of the
chips have been caused by partitioning not on a 1K boundary.

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