ethtool: bring back missing comma in netdev features strings

The issue was introduced in commit eed2a12f.
Signed-off-by: Franco Fichtner <franco@lastsummer.de>
Acked-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/ethtool.c

@@ -361,7 +361,7 @@ static const char netdev_features_strings[ETHTOOL_DEV_FEATURE_WORDS * 32][ETH_GS
 	/* NETIF_F_NTUPLE */          "rx-ntuple-filter",
 	/* NETIF_F_RXHASH */          "rx-hashing",
 	/* NETIF_F_RXCSUM */          "rx-checksum",
-	/* NETIF_F_NOCACHE_COPY */    "tx-nocache-copy"
+	/* NETIF_F_NOCACHE_COPY */    "tx-nocache-copy",
 	/* NETIF_F_LOOPBACK */        "loopback",
 };