batman-adv: avoid useless return in void functions

Cc: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: NAntonio Quartulli <antonio@meshcoding.com>
Signed-off-by: NMarek Lindner <mareklindner@neomailbox.ch>

net/batman-adv/debugfs.c

@@ -233,7 +233,6 @@ static int batadv_debug_log_setup(struct batadv_priv *bat_priv)
 
 static void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)
 {
-	return;
 }
 #endif
 

net/batman-adv/multicast.h

@@ -50,7 +50,6 @@ void batadv_mcast_purge_orig(struct batadv_orig_node *orig_node);
 
 static inline void batadv_mcast_mla_update(struct batadv_priv *bat_priv)
 {
-	return;
 }
 
 static inline enum batadv_forw_mode
@@ -67,12 +66,10 @@ static inline int batadv_mcast_init(struct batadv_priv *bat_priv)
 
 static inline void batadv_mcast_free(struct batadv_priv *bat_priv)
 {
-	return;
 }
 
 static inline void batadv_mcast_purge_orig(struct batadv_orig_node *orig_node)
 {
-	return;
 }
 
 #endif /* CONFIG_BATMAN_ADV_MCAST */