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_synctty.c b/drivers/net/ppp_synctty.c
index 52938da..4c95ec3 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -97,9 +97,9 @@
 static void ppp_sync_input(struct syncppp *ap, const unsigned char *buf,
 			   char *flags, int count);
 
-static struct ppp_channel_ops sync_ops = {
-	ppp_sync_send,
-	ppp_sync_ioctl
+static const struct ppp_channel_ops sync_ops = {
+	.start_xmit = ppp_sync_send,
+	.ioctl      = ppp_sync_ioctl,
 };
 
 /*