qcacld-3.0: Donot access invalid wiphy band

In wlan_hdd_get_wiphy_channel(), Donot access
60 Ghz which are not part of wiphy.

Change-Id: Ie8249bdcc7c4fb66744a9b16f2c194e9ab60dd1b
CRs-Fixed: 2984046

core/hdd/src/wlan_hdd_hostapd.c

@@ -4946,6 +4946,10 @@ static struct ieee80211_channel *wlan_hdd_get_wiphy_channel(
 	struct ieee80211_channel *wiphy_channel = NULL;
 
 	for (band_num = 0; band_num < HDD_NUM_NL80211_BANDS; band_num++) {
+		if (!wiphy->bands[band_num]) {
+			hdd_debug("Band %d not part of wiphy", band_num);
+			continue;
+		}
 		for (channel_num = 0; channel_num <
 				wiphy->bands[band_num]->n_channels;
 				channel_num++) {