sky2: fe+ chip support

Add support for newest Marvell chips.
The Yukon FE plus chip is found in some not yet released laptops.
Tested on hardware evaluation boards.

This version of the patch is for 2.6.23. It supersedes
the two previous patches that are sitting in netdev-2.6 (upstream branch).

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