dsa: Add TAG protocol to tag ops

In order that we can match the tagging protocol a switch driver
request to the tagger, we need to know what protocol the tagger
supports. Add this information to the ops structure.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

v2
More tag protocol to end of structure to keep hot members at the beginning.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/dsa.h b/include/net/dsa.h
index 8f3d5e0..720036f 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -70,6 +70,7 @@ struct dsa_device_ops {
 			    int *offset);
 	unsigned int overhead;
 	const char *name;
+	enum dsa_tag_protocol proto;
 };
 
 #define DSA_TAG_DRIVER_ALIAS "dsa_tag-"