bnxt_en: Add missing skb_mark_for_recycle() in bnxt_rx_vlan()

If bnxt_rx_vlan() fails because the VLAN protocol ID is invalid,
the SKB is freed but we're missing the call to recycle it.  This
may cause the warning:

"page_pool_release_retry() stalled pool shutdown"

Add the missing skb_mark_for_recycle() in bnxt_rx_vlan().

Fixes: 86b05508 ("bnxt_en: Use the unified RX page pool buffers for XDP and non-XDP")
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>