qcacld-3.0: Add support for CFG80211_REMOVE_IEEE80211_BACKPORT

CFG80211_REMOVE_IEEE80211_BACKPORT is added to indicate
backport of Change-Id: 57fbcce37be7c1d2622b56587c10ade00e96afa3
from upstream 4.7 kernel to 4.4.

Hence add this flag CFG80211_REMOVE_IEEE80211_BACKPORT to
support this compilation. Also introduce HDD_NUM_NL80211_BANDS.

Change-Id: I60a15a1273f939a0a288d08d03ccb5bf1bdcc429
CRs-Fixed: 2087917
diff --git a/core/hdd/src/wlan_hdd_ocb.c b/core/hdd/src/wlan_hdd_ocb.c
index e467a27..dce4918 100644
--- a/core/hdd/src/wlan_hdd_ocb.c
+++ b/core/hdd/src/wlan_hdd_ocb.c
@@ -129,7 +129,7 @@
 	struct ieee80211_supported_band *current_band;
 	struct ieee80211_channel *current_channel;
 
-	for (band_idx = 0; band_idx < NUM_NL80211_BANDS; band_idx++) {
+	for (band_idx = 0; band_idx < HDD_NUM_NL80211_BANDS; band_idx++) {
 		current_band = wiphy->bands[band_idx];
 		if (!current_band)
 			continue;