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/common.c b/net/atm/common.c
index c865517..d34edbe 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -262,7 +262,7 @@
 }
 
 
-static int check_ci(struct atm_vcc *vcc, short vpi, int vci)
+static int check_ci(const struct atm_vcc *vcc, short vpi, int vci)
 {
 	struct hlist_head *head = &vcc_hash[vci &
 					(VCC_HTABLE_SIZE - 1)];
@@ -290,7 +290,7 @@
 }
 
 
-static int find_ci(struct atm_vcc *vcc, short *vpi, int *vci)
+static int find_ci(const struct atm_vcc *vcc, short *vpi, int *vci)
 {
 	static short p;        /* poor man's per-device cache */
 	static int c;
@@ -646,7 +646,7 @@
 }
 
 
-static int check_tp(struct atm_trafprm *tp)
+static int check_tp(const struct atm_trafprm *tp)
 {
 	/* @@@ Should be merged with adjust_tp */
 	if (!tp->traffic_class || tp->traffic_class == ATM_ANYCLASS) return 0;
@@ -663,7 +663,7 @@
 }
 
 
-static int check_qos(struct atm_qos *qos)
+static int check_qos(const struct atm_qos *qos)
 {
 	int error;