esp_wifi_set_band() function

Set WiFi current band. @attention 1. This API is only operational when the WiFi band mode is configured to 2.4G + 5G (WIFI_BAND_MODE_AUTO) @attention 2. When device is in STA mode, this API should not be called when STA is scanning or connecting to an external AP @attention 3. When device is in softAP mode, this API should not be called when softAP has connected to external STAs @attention 4. When device is in STA+softAP mode, this API should not be called when in the scenarios described above @attention 5. It is recommended not to use this API. If you want to change the current band, you can use esp_wifi_set_channel instead.