qcacld-3.0: Set channel BW as 20 MHz for IBSS in 2.4 GHz

Propagation from qcacld-2.0 to qcacld-3.0.

The device supports only 20 MHz while operating in IBSS
mode in 2.4 GHz band. There is no support in firmware to
do OBSS scan in STA/IBSS mode. Thus, the device will not
start IBSS when the configured bandwidth is other than
20 MHz in 2.4 GHz band.

Update channel width as 20 MHz if the device is in IBSS
mode and is operating in 2.4 GHz.

Change-Id: I01fa0df44f8b6f9ada835c0fc80a46eb0da6d6d7
CRs-Fixed: 1009922
(cherry picked from commit 5167d6c9b4271f08d3e819a0e9a7da1142630094)
(cherry picked from commit 5baf73480e91e68a2b5dfbe2a6981003d064fc9c)

core/hdd/src/wlan_hdd_cfg80211.c

@@ -10595,6 +10595,13 @@ static int wlan_hdd_cfg80211_connect_start(hdd_adapter_t *pAdapter,
 			}
 			pRoamProfile->ch_params.ch_width =
 				hdd_map_nl_chan_width(ch_width);
+			/*
+			 * In IBSS mode while operating in 2.4 GHz,
+			 * the device supports only 20 MHz.
+			 */
+			if (CDS_IS_CHANNEL_24GHZ(operatingChannel))
+				pRoamProfile->ch_params.ch_width =
+					CH_WIDTH_20MHZ;
 			hdd_select_cbmode(pAdapter, operatingChannel,
 					  &pRoamProfile->ch_params);
 		}