[ Upstream commit 4e9016be ]

If the rx-offload skb_queue is full or the skb allocation fails (due to OOM),
the mailbox contents is discarded.

This patch adds the incrementing of the rx_fifo_errors statistics counter.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>