net: dsa: qca8k: do not write port mask twice in bridge join/leave

qca8k_port_bridge_join() set QCA8K_PORT_LOOKUP_CTRL() for i == port twice,
once in the loop handling all other port's masks, and finally at the end
with the accumulated port_mask.

The first time it would incorrectly set the port's own bit in the mask,
only to correct the mistake a moment later. qca8k_port_bridge_leave() had
the same issue, but here the regmap_clear_bits() was a no-op rather than
setting an unintended value.

Remove the duplicate assignment by skipping the whole loop iteration for
i == port. The unintended bit setting doesn't seem to have any negative
effects (even when not reverted right away), so the change is submitted
as a simple cleanup rather than a fix.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca/qca8k-common.c

@@ -653,6 +653,8 @@ int qca8k_port_bridge_join(struct dsa_switch *ds, int port,
 	port_mask = BIT(cpu_port);
 
 	for (i = 0; i < QCA8K_NUM_PORTS; i++) {
+		if (i == port)
+			continue;
 		if (dsa_is_cpu_port(ds, i))
 			continue;
 		if (!dsa_port_offloads_bridge(dsa_to_port(ds, i), &bridge))
@@ -665,7 +667,6 @@ int qca8k_port_bridge_join(struct dsa_switch *ds, int port,
 				      BIT(port));
 		if (ret)
 			return ret;
-		if (i != port)
 		port_mask |= BIT(i);
 	}
 
@@ -685,6 +686,8 @@ void qca8k_port_bridge_leave(struct dsa_switch *ds, int port,
 	cpu_port = dsa_to_port(ds, port)->cpu_dp->index;
 
 	for (i = 0; i < QCA8K_NUM_PORTS; i++) {
+		if (i == port)
+			continue;
 		if (dsa_is_cpu_port(ds, i))
 			continue;
 		if (!dsa_port_offloads_bridge(dsa_to_port(ds, i), &bridge))