[PATCH] sky2: fragmented receive for large MTU

Use hardware support for chained receive to break up large frames
into multiple pages. This avoids having to do a mult-page allocation
that can fail on a busy system due to fragmented memory.

For normal size MTU, this code behaves the same.

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