ble_gatts: update fan mode definitions

Author: redchenjs

main/src/user/ble_gatts.c

@@ -208,7 +208,7 @@ static void profile_fan_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t
             memcpy(rsp.attr_value.value, &desc_val_fan, sizeof(desc_val_fan));
         } else {
             rsp.attr_value.len = 8;
-            rsp.attr_value.value[0] = 0x02;
+            rsp.attr_value.value[0] = 0x04;
             rsp.attr_value.value[1] = 0x00;
             rsp.attr_value.value[2] = 0x00;
             rsp.attr_value.value[3] = 0x00;