ppp: make channel_ops const

The PPP channel ops structure should be const.
Cleanup the declarations to use standard C99 format.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index 6c2e8fa..af50a53 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -108,9 +108,9 @@
 static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
 			   int len, int inbound);
 
-static struct ppp_channel_ops async_ops = {
-	ppp_async_send,
-	ppp_async_ioctl
+static const struct ppp_channel_ops async_ops = {
+	.start_xmit = ppp_async_send,
+	.ioctl      = ppp_async_ioctl,
 };
 
 /*