ks8851: Fix NOHZ local_softirq_pending 08 warning

This fix a similar problem as in 72092cc4
and 481a8199 ("can:
fix NOHZ local_softirq_pending 08 warning"). This fix replaces netif_rx()
with netif_rx_ni() which has to be used from process/softirq context.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>