[PATCH] rtnetlink: Fix missing error code in rtnl_bridge_notify()

The error code is missing in this code scenario, add the error code
'-EINVAL' to the return value 'err'.

Eliminate the follow smatch warning:

net/core/rtnetlink.c:4834 rtnl_bridge_notify() warn: missing error code
'err'.

Reported-by: Abaci Robot <redacted>
Signed-off-by: Jiapeng Chong <redacted>
---
 net/core/rtnetlink.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 714d5fa..3e84279 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c

@@ -4842,8 +4842,10 @@ static int rtnl_bridge_notify(struct net_device *dev)
 	if (err < 0)
 		goto errout;
 
-	if (!skb->len)
+	if (!skb->len) {
+		err = -EINVAL;
 		goto errout;
+	}
 
 	rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC);
 	return 0;

-- 
1.8.3.1