net: mvpp2: Add missing VLAN tag detection

Marvell PPv2 Header Parser sets some bits in the 'result_info' field in
each lookup iteration, to identify different packet attributes such as
DSA / VLAN tag, protocol infos, etc. This is used in further
classification stages in the controller.

It's the DSA tag detection entry that is in charge of detecting when there
is a single VLAN tag.

This commits adds the missing update of the result_info in this case.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2.c

@@ -2128,6 +2128,9 @@ static void mvpp2_prs_dsa_tag_set(struct mvpp2 *priv, int port, bool add,
 				mvpp2_prs_sram_ai_update(&pe, 0,
 							MVPP2_PRS_SRAM_AI_MASK);
 
+			/* Set result info bits to 'single vlan' */
+			mvpp2_prs_sram_ri_update(&pe, MVPP2_PRS_RI_VLAN_SINGLE,
+						 MVPP2_PRS_RI_VLAN_MASK);
 			/* If packet is tagged continue check vid filtering */
 			mvpp2_prs_sram_next_lu_set(&pe, MVPP2_PRS_LU_VID);
 		} else {