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/sysfs.c b/net/wireless/sysfs.c
index 15feaeb..efe3c5c 100644
--- a/net/wireless/sysfs.c
+++ b/net/wireless/sysfs.c
@@ -31,7 +31,7 @@
 	return sprintf(buf, fmt "\n", dev_to_rdev(dev)->member);	\
 }
 
-SHOW_FMT(index, "%d", idx);
+SHOW_FMT(index, "%d", wiphy_idx);
 SHOW_FMT(macaddress, "%pM", wiphy.perm_addr);
 
 static struct device_attribute ieee80211_dev_attrs[] = {