Fix minimum size of buxton control messages
Fix minimum size of buxton control messages

Previously it was too large, meaning anything other than a string
was not being deserialized, as it was considered an invalid message.

Signed-off-by: Michael Ikey Doherty <15e2f59c60e9d84348e78a87e24660774f739add@intel.com>

sofar/buxton,sofar/buxton