8139cp: properly config rx mode after resuming

Rx mode should be reset after resming, so unconditionally updating rx
mode rather than conditionally updating based on the value we
remembered, otherwise unexpected value may be used by the nic after
resuming.

btw. I find and test this when debugging guest hibernation in qemu, as
I did not have a 8139cp card in hand, this patch is untested in a
physical 8139cp card, plase review it carefully.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>