yam: fix possible memory leak in yam_init_driver

BugLink: https://bugs.launchpad.net/bugs/1885932

[ Upstream commit 98749b71 ]

If register_netdev(dev) fails, free_netdev(dev) needs
to be called, otherwise a memory leak will occur.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

drivers/net/hamradio/yam.c

@@ -1160,6 +1160,7 @@ static int __init yam_init_driver(void)
 		err = register_netdev(dev);
 		if (err) {
 			printk(KERN_WARNING "yam: cannot register net device %s\n", dev->name);
+			free_netdev(dev);
 			goto error;
 		}
 		yam_devs[i] = dev;