qcacld-3.0: Add vendor command attribute for roam hand-off delay

User can configure roam hand-off delay value using the new vendor
attribute introduced as part roam vendor command.
This change gets the configured value and sends it to firmware.
And firmware delays the roam Hand-off (in msec) by the specified
duration to receive pending RX frames from the current BSS.

Change-Id: Ic328c077cba06532ee8ffed12cde072c816b92e0
CRs-Fixed: 3329964

components/mlme/dispatcher/inc/wlan_mlme_public_struct.h

@@ -1903,6 +1903,7 @@ struct fw_scan_channels {
  * during wakeup.
  * @beaconloss_timeout_onsleep: time in sec to configure FW BMISS event
  * during sleep.
+ * @roam_ho_delay_config: Roam HO delay value
  */
 struct wlan_mlme_lfr_cfg {
 	bool mawc_roam_enabled;
@@ -2025,6 +2026,7 @@ struct wlan_mlme_lfr_cfg {
 	bool enable_ft_over_ds;
 	uint8_t beaconloss_timeout_onwakeup;
 	uint8_t beaconloss_timeout_onsleep;
+	uint16_t roam_ho_delay_config;
 };
 
 /**