cfg80211: fix regulatory code const

A few pointers and structures in the regulatory code are const,
but because it wasn't done properly a whole bunch of bogus
casts were needed to compile without warning. Mark everything
const properly to avoid that kind of junk code.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/reg.h b/net/wireless/reg.h
index b169815..a333628 100644
--- a/net/wireless/reg.h
+++ b/net/wireless/reg.h
@@ -2,12 +2,12 @@
 #define __NET_WIRELESS_REG_H
 
 extern struct mutex cfg80211_reg_mutex;
-bool is_world_regdom(char *alpha2);
-bool reg_is_valid_request(char *alpha2);
+bool is_world_regdom(const char *alpha2);
+bool reg_is_valid_request(const char *alpha2);
 
 int regulatory_init(void);
 void regulatory_exit(void);
 
-int set_regdom(struct ieee80211_regdomain *rd);
+int set_regdom(const struct ieee80211_regdomain *rd);
 
 #endif  /* __NET_WIRELESS_REG_H */