Rarely the bluetooth firmware is not loaded properly and causes
errors in the configuration steps. This verification makes sure
the firmware was loaded and is functional, if not we start the
retry mechanism with the default baudrate to avoid the firmware
corruption in the upload process.
https://jira.digi.com/browse/DEL-3711
Signed-off-by: Arturo Buzarra <arturo.buzarra@digi.com>