nfs: plug memory leak when ->prepare_layoutcommit fails

"data" is currently leaked when the prepare_layoutcommit operation
returns an error. Put the cred before taking the spinlock in that
case, take the lock and then goto out_unlock which will drop the
lock and then free "data".
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/pnfs.c

@@ -2221,13 +2221,12 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
 	if (ld->prepare_layoutcommit) {
 		status = ld->prepare_layoutcommit(&data->args);
 		if (status) {
+			put_rpccred(data->cred);
 			spin_lock(&inode->i_lock);
 			set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
 			if (end_pos > nfsi->layout->plh_lwb)
 				nfsi->layout->plh_lwb = end_pos;
-			spin_unlock(&inode->i_lock);
-			put_rpccred(data->cred);
-			goto clear_layoutcommitting;
+			goto out_unlock;
 		}
 	}