net/smc: fix error return code in smc_setsockopt()

Fix to return error code -EINVAL instead of 0 if optlen is invalid.

Fixes: 01d2f7e2cdd3 ("net/smc: sockopts TCP_NODELAY and TCP_CORK")
Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/smc/af_smc.c

···
 		return rc;
 
 	if (optlen < sizeof(int))
-		return rc;
+		return -EINVAL;
 	get_user(val, (int __user *)optval);
 
 	lock_sock(sk);