batman-adv: remove packed from batadv_ogm_packet

As we decreased the struct size from 26 to 24 byte, we can remove
__packed as the compiler will not add any more padding.
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

net/batman-adv/packet.h

@@ -175,7 +175,10 @@ struct batadv_ogm_packet {
 	uint8_t  reserved;
 	uint8_t  tq;
 	__be16   tvlv_len;
-} __packed;
+	/* __packed is not needed as the struct size is divisible by 4,
+	 * and the largest data type in this struct has a size of 4.
+	 */
+};
 
 #define BATADV_OGM_HLEN sizeof(struct batadv_ogm_packet)