nfs: Add missing release on error in nfs_lock_and_join_requests()

Call nfs_release_request() on this error path before returning.

Fixes: c3f2235 ("nfs: fold nfs_folio_find_and_lock_request into nfs_lock_and_join_requests")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/3aaaa3d5-1c8a-41e4-98c7-717801ddd171@stanley.mountain
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Author: Dan Carpenter

fs/nfs/write.c

@@ -579,8 +579,10 @@ static struct nfs_page *nfs_lock_and_join_requests(struct folio *folio)
 
 	while (!nfs_lock_request(head)) {
 		ret = nfs_wait_on_request(head);
-		if (ret < 0)
+		if (ret < 0) {
+			nfs_release_request(head);
 			return ERR_PTR(ret);
+		}
 	}
 
 	/* Ensure that nobody removed the request before we locked it */