net: dsa: remove dp->priv

All current in-tree uses of dp->priv have been replaced with
ds->tagger_data, which provides for a safer API especially when the
connection isn't the regular 1:1 link between one switch driver and one
tagging protocol driver, but could be either one switch to many taggers,
or many switches to one tagger.

Therefore, we can remove this unused pointer.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -276,12 +276,6 @@ struct dsa_port {
 
 	struct list_head list;
 
-	/*
-	 * Give the switch driver somewhere to hang its per-port private data
-	 * structures (accessible from the tagger).
-	 */
-	void *priv;
-
 	/*
 	 * Original copy of the master netdev ethtool_ops
 	 */