crypto: algif_aead - fix uninitialized variable warning

In case the user provided insufficient data, the code may return
prematurely without any operation. In this case, the processed
data indicated with outlen is zero.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/algif_aead.c

@@ -420,7 +420,7 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg,
 	unsigned int i, reqlen = GET_REQ_SIZE(tfm);
 	int err = -ENOMEM;
 	unsigned long used;
-	size_t outlen;
+	size_t outlen = 0;
 	size_t usedpages = 0;
 
 	lock_sock(sk);