atm: use const where reasonable

From: Mitchell Blank Jr <mitch@sfgoth.com>

Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/atm/addr.h b/net/atm/addr.h
index f39433a..6837e9e 100644
--- a/net/atm/addr.h
+++ b/net/atm/addr.h
@@ -10,9 +10,9 @@
 #include <linux/atmdev.h>
 
 void atm_reset_addr(struct atm_dev *dev, enum atm_addr_type_t type);
-int atm_add_addr(struct atm_dev *dev, struct sockaddr_atmsvc *addr,
+int atm_add_addr(struct atm_dev *dev, const struct sockaddr_atmsvc *addr,
 		 enum atm_addr_type_t type);
-int atm_del_addr(struct atm_dev *dev, struct sockaddr_atmsvc *addr,
+int atm_del_addr(struct atm_dev *dev, const struct sockaddr_atmsvc *addr,
 		 enum atm_addr_type_t type);
 int atm_get_addr(struct atm_dev *dev, struct sockaddr_atmsvc __user *buf,
 		 size_t size, enum atm_addr_type_t type);