[HELP] XIAO ESP32C3 fails to advertise over Bluetooth

### Description

Build:

```console
$ ./tools/configure.sh esp32c3-xiao:ble
$ make -j
```

In the USB console connected to the device:

```console
nsh> ifconfig
bnep0 Link encap:UNSPEC at DOWN mtu -9
inet addr:0.0.0.0 DRaddr:0.0.0.0 Mask:0.0.0.0

nsh> ifup bnep0
ifup bnep0...OK
nsh> bt bnep0 advertise start
hci_cmd_done: WARNING: status 12
bt_hci_cmd_send_sync: ERROR: Failed get return parameters
ERROR: ioctl(SIOCBTADVSTART) failed: 5
```

What is the proper way to test advertising? I would like to see if the device can show up on my mobile phone when I have it searching for new devices.

### Verification

- [x] I have verified before submitting the report.