net: dsa: tag_sja1105: absorb entire sja1105_vlan_rcv() into dsa_8021q_rcv()

net: dsa: tag_sja1105: absorb entire sja1105_vlan_rcv() into dsa_8021q_rcv()

tag_sja1105 has a wrapper over dsa_8021q_rcv(): sja1105_vlan_rcv(),
which determines whether the packet came from a bridge with
vlan_filtering=1 (the case resolved via
dsa_find_designated_bridge_port_by_vid()), or if it contains a tag_8021q
header.

Looking at a new tagger implementation for vsc73xx, based also on
tag_8021q, it is becoming clear that the logic is needed there as well.
So instead of forcing each tagger to wrap around dsa_8021q_rcv(), let's
merge the logic into the core.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
Link: https://patch.msgid.link/20240713211620.1125910-5-paweldembicki@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>