drivers/net/niu.c: adjust array index

Convert array index from the loop bound to the loop index.

A simplified version of the semantic patch that fixes this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e1,e2,ar;
@@

for(e1 = 0; e1 < e2; e1++) { <...
  ar[
- e2
+ e1
  ]
  ...> }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/niu.c b/drivers/net/niu.c
index cd6c231..ed47585 100644
--- a/drivers/net/niu.c
+++ b/drivers/net/niu.c
@@ -9201,7 +9201,7 @@
 
 	first_chan = 0;
 	for (i = 0; i < port; i++)
-		first_chan += parent->rxchan_per_port[port];
+		first_chan += parent->rxchan_per_port[i];
 	num_chan = parent->rxchan_per_port[port];
 
 	for (i = first_chan; i < (first_chan + num_chan); i++) {
@@ -9217,7 +9217,7 @@
 
 	first_chan = 0;
 	for (i = 0; i < port; i++)
-		first_chan += parent->txchan_per_port[port];
+		first_chan += parent->txchan_per_port[i];
 	num_chan = parent->txchan_per_port[port];
 	for (i = first_chan; i < (first_chan + num_chan); i++) {
 		err = niu_ldg_assign_ldn(np, parent,