Appearently, CanBusUtil was inspired by SocketCANs cansend,
and this does interpret all input as hexadecimal.

Further, the data byte following the hash mark '#' were
already used in hex, so let's be consequent.

Change-Id: I21324eb540ae2792f747dbae49865973d182d2d9
Reviewed-by: Denis Shienkov <denis.shienkov@gmail.com>
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>