atl1c: Improve driver not to do order 4 GFP_ATOMIC allocation

atl1c driver is doing order-4 allocation with GFP_ATOMIC
priority. That often breaks  networking after resume. Switch to
GFP_KERNEL. Still not ideal, but should be significantly better.

atl1c_setup_ring_resources() is called from .open() function, and
already uses GFP_KERNEL, so this change is safe.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>