af_unix: call proto_unregister() in the error path in af_unix_init()

af_unix: call proto_unregister() in the error path in af_unix_init()

[ Upstream commit 73e341e0281a35274629e9be27eae2f9b1b492bf ]

If register unix_stream_proto returns error, unix_dgram_proto needs
be unregistered.

Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>