libertas: make lbs_process_event() void

Fix the following coccicheck warning:

drivers/net/wireless/marvell/libertas/cmdresp.c:225:5-8: Unneeded
variable: "ret". Return "0" on line 355
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200413082022.22380-1-yanaijie@huawei.com

drivers/net/wireless/marvell/libertas/cmd.h

@@ -76,7 +76,7 @@ void lbs_mac_event_disconnected(struct lbs_private *priv,
 
 /* Events */
 
-int lbs_process_event(struct lbs_private *priv, u32 event);
+void lbs_process_event(struct lbs_private *priv, u32 event);
 
 
 /* Actual commands */

drivers/net/wireless/marvell/libertas/cmdresp.c

@@ -220,9 +220,8 @@ int lbs_process_command_response(struct lbs_private *priv, u8 *data, u32 len)
 	return ret;
 }
 
-int lbs_process_event(struct lbs_private *priv, u32 event)
+void lbs_process_event(struct lbs_private *priv, u32 event)
 {
-	int ret = 0;
 	struct cmd_header cmd;
 
 	switch (event) {
@@ -351,6 +350,4 @@ int lbs_process_event(struct lbs_private *priv, u32 event)
 		netdev_alert(priv->dev, "EVENT: unknown event id %d\n", event);
 		break;
 	}
-
-	return ret;
 }