dm9601: Fix multicast hash table handling

The loop forgot to walk the net->mc_list list, so only the first
multicast address was programmed into the hash table.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/usb/dm9601.c b/drivers/net/usb/dm9601.c
index 0343b00..01660f6 100644
--- a/drivers/net/usb/dm9601.c
+++ b/drivers/net/usb/dm9601.c
@@ -354,7 +354,7 @@
 		struct dev_mc_list *mc_list = net->mc_list;
 		int i;
 
-		for (i = 0; i < net->mc_count; i++) {
+		for (i = 0; i < net->mc_count; i++, mc_list = mc_list->next) {
 			u32 crc = ether_crc(ETH_ALEN, mc_list->dmi_addr) >> 26;
 			hashes[crc >> 3] |= 1 << (crc & 0x7);
 		}