add psu brownout check to do_checks
add psu brownout check to do_checks

madcowswe/ODrive,madcowswe/ODriveFirmware,madcowswe/ODriveFirmware,madcowswe/ODriveFirmware,madcowswe/ODriveFirmware,madcowswe/ODrive,madcowswe/ODrive,madcowswe/ODrive,madcowswe/ODrive