MT7615 DBDC config via luci web not work property

1. cannot change channel
2. cannot scan 2.4g

radio0 should be 11g mode but default is 11ac
radio1 should be 11ac mode but default is not.

I have to change radio0 to 11g and radio1 to 11ac, so that it works

the ubus resault:

[{
	"id": 380,
	"jsonrpc": "2.0",
	"result": {
		"hostapd.wlan0": {
			"wps_status": [],
			"list_bans": [],
			"switch_chan": {
				"center_freq1": "unknown",
				"center_freq2": "unknown",
				"ht": "unknown",
				"freq": "unknown",
				"sec_channel_offset": "unknown",
				"bandwidth": "unknown",
				"vht": "unknown",
				"block_tx": "unknown",
				"bcn_count": "unknown"
			},
			"rrm_nr_list": [],
			"del_client": {
				"deauth": "unknown",
				"addr": "object",
				"ban_time": "unknown",
				"reason": "unknown"
			},
			"get_clients": [],
			"bss_mgmt_enable": {
				"neighbor_report": "unknown",
				"bss_transition": "unknown",
				"beacon_report": "unknown"
			},
			"rrm_nr_set": {
				"list": "unknown"
			},
			"set_vendor_elements": {
				"vendor_elements": "object"
			},
			"rrm_nr_get_own": [],
			"reload": [],
			"rrm_beacon_req": {
				"addr": "object",
				"ssid": "object",
				"op_class": "unknown",
				"channel": "unknown",
				"bssid": "object",
				"duration": "unknown",
				"mode": "unknown"
			},
			"notify_response": {
				"notify_response": "unknown"
			},
			"wps_cancel": [],
			"wps_start": [],
			"get_features": [],
			"update_beacon": [],
			"wnm_disassoc_imminent": {
				"duration": "unknown",
				"neighbors": "unknown",
				"abridged": "unknown",
				"addr": "object"
			}
		},
		"hostapd.wlan1": {
			"wps_status": [],
			"list_bans": [],
			"switch_chan": {
				"center_freq1": "unknown",
				"center_freq2": "unknown",
				"ht": "unknown",
				"freq": "unknown",
				"sec_channel_offset": "unknown",
				"bandwidth": "unknown",
				"vht": "unknown",
				"block_tx": "unknown",
				"bcn_count": "unknown"
			},
			"rrm_nr_list": [],
			"del_client": {
				"deauth": "unknown",
				"addr": "object",
				"ban_time": "unknown",
				"reason": "unknown"
			},
			"get_clients": [],
			"bss_mgmt_enable": {
				"neighbor_report": "unknown",
				"bss_transition": "unknown",
				"beacon_report": "unknown"
			},
			"rrm_nr_set": {
				"list": "unknown"
			},
			"set_vendor_elements": {
				"vendor_elements": "object"
			},
			"rrm_nr_get_own": [],
			"reload": [],
			"rrm_beacon_req": {
				"addr": "object",
				"ssid": "object",
				"op_class": "unknown",
				"channel": "unknown",
				"bssid": "object",
				"duration": "unknown",
				"mode": "unknown"
			},
			"notify_response": {
				"notify_response": "unknown"
			},
			"wps_cancel": [],
			"wps_start": [],
			"get_features": [],
			"update_beacon": [],
			"wnm_disassoc_imminent": {
				"duration": "unknown",
				"neighbors": "unknown",
				"abridged": "unknown",
				"addr": "object"
			}
		}
	}
}]

Start by reproducing the MT7615 DBDC configuration through the LuCI web interface and inspecting the ubus output for hostapd.wlan0 and hostapd.wlan1. Trace how the requested radio modes and channel settings are passed through the configuration path; done means radio0 defaults to 11g, radio1 defaults to 11ac, channel changes work, and 2.4 GHz scanning succeeds.