Fix wifi delete not working when importing wifi config from OFW

[medeirosT]

Add update_config=1 to make sure wpa_supplicant can update its config and not silently fail.

See https://raw.githubusercontent.com/zephyrproject-rtos/hostap/d945ddd368085f255e68328f2d3b020ceea359af/wpa_supplicant/ctrl_iface.c:

#ifndef CONFIG_NO_CONFIG_WRITE
static int wpa_supplicant_ctrl_iface_save_config(struct wpa_supplicant *wpa_s)
{
	int ret;

	if (!wpa_s->conf->update_config) {
		wpa_printf(MSG_DEBUG, "CTRL_IFACE: SAVE_CONFIG - Not allowed "
			   "to update configuration (update_config=0)");
		return -1;
	}

	ret = wpa_config_write(wpa_s->confname, wpa_s->conf);
	if (ret) {
		wpa_printf(MSG_DEBUG, "CTRL_IFACE: SAVE_CONFIG - Failed to "
			   "update configuration");
	} else {
		wpa_printf(MSG_DEBUG, "CTRL_IFACE: SAVE_CONFIG - Configuration"
			   " updated");
	}

	return ret;
}
#endif /* CONFIG_NO_CONFIG_WRITE */

it fails if update_config is either not present or set to 0

Should fix the issue of deleting the imported wifi from OFW