e1000: set E1000_ICR_INT_ASSERTED only for 8257x

E1000_ICR_INT_ASSERTED were introduced only for 8257x, so we need to
check the E1000_DEVID before setting this bit in ICS.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
