NFS: remove unneeded check in decode_devicenotify_args()

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Overflow check in not needed anymore after we switch to kmalloc_array().
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: a4f743a6 ("NFSv4.1: Convert open-coded array allocation calls to kmalloc_array()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/callback_xdr.c

@@ -271,10 +271,6 @@ __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 	n = ntohl(*p++);
 	if (n == 0)
 		goto out;
-	if (n > ULONG_MAX / sizeof(*args->devs)) {
-		status = htonl(NFS4ERR_BADXDR);
-		goto out;
-	}
 
 	args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 	if (!args->devs) {