cfg80211: rename cfg80211_registered_device's idx to wiphy_idx

Makes it clearer to read when comparing to ifidx

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 5d0c682..1783781 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -37,7 +37,7 @@
 	enum environment_cap env;
 
 	/* wiphy index, internal only */
-	int idx;
+	int wiphy_idx;
 
 	/* associate netdev list */
 	struct mutex devlist_mtx;