bnxt_en: Fix DMA unmapping of the RX buffers in XDP mode during shutdown.

bnxt_en: Fix DMA unmapping of the RX buffers in XDP mode during shutdown.

Orabug: 26402533, 26325599, 26366387

In bnxt_free_rx_skbs(), which is called to free up all RX buffers during
shutdown, we need to unmap the page if we are running in XDP mode.

Fixes: c61fb99cae51 ("bnxt_en: Add RX page mode support.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 3ed3a83e3f3871c57b18cef09b148e96921236ed)
Signed-off-by: Brian Maly <brian.maly@oracle.com>
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Conflicts:
	drivers/net/ethernet/broadcom/bnxt/bnxt.c