mv643xx_eth: Hook up mv643xx_get_sset_count

Commit b9f2c044 replaced mv643xx_get_stats_count() with
mv643xx_get_sset_count(), but forgot to hook it up.

drivers/net/mv643xx_eth.c:2678: warning: mv643xx_get_sset_count defined but not used
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>

drivers/net/mv643xx_eth.c

@@ -2742,6 +2742,7 @@ static const struct ethtool_ops mv643xx_ethtool_ops = {
 	.get_drvinfo            = mv643xx_get_drvinfo,
 	.get_link               = mv643xx_eth_get_link,
 	.set_sg			= ethtool_op_set_sg,
+	.get_sset_count		= mv643xx_get_sset_count,
 	.get_ethtool_stats      = mv643xx_get_ethtool_stats,
 	.get_strings            = mv643xx_get_strings,
 	.nway_reset		= mv643xx_eth_nway_restart,