l2tp: kzalloc with swapped params in l2tp_dfs_seq_open

  'sparse' spotted that the parameters to kzalloc in l2tp_dfs_seq_open
were swapped.

Tested on current git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
at 1792f17b  build, boots and I can see that directory,
but there again I could see /sys/kernel/debug/l2tp with it swapped; I don't have
any l2tp in use.
Signed-off-by: NDr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/l2tp/l2tp_debugfs.c

@@ -249,7 +249,7 @@ static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
 	struct seq_file *seq;
 	int rc = -ENOMEM;
 
-	pd = kzalloc(GFP_KERNEL, sizeof(*pd));
+	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
 	if (pd == NULL)
 		goto out;