qcacld-3.0: Add a new INI RoamCU_6GRSSIRange

Add support to parse a new INI named
"bss_load_trigger_6g_rssi_threshold/RoamCU_6GRSSIRange"
and send its value to FW via WMI_ROAM_BSS_LOAD_CONFIG_CMDID.

Min, Max and default value of this INI:
Min: -120
Max: 0
Default: -70

Change-Id: I9aa99d887553de4022fc0a31dc0644601cd340d6
CRs-Fixed: 3225548

components/target_if/connection_mgr/src/target_if_cm_roam_offload.c

@@ -863,6 +863,9 @@ target_if_cm_roam_bss_load_config(wmi_unified_t wmi_handle,
 	db2dbm_enabled = wmi_service_enabled(wmi_handle,
 					     wmi_service_hw_db2dbm_support);
 	if (!db2dbm_enabled) {
+		req->rssi_threshold_6ghz -= NOISE_FLOOR_DBM_DEFAULT;
+		req->rssi_threshold_6ghz &= 0x000000ff;
+
 		req->rssi_threshold_5ghz -= NOISE_FLOOR_DBM_DEFAULT;
 		req->rssi_threshold_5ghz &= 0x000000ff;