Memory corruption

[ilcaprone3d]

There are problems in many methods using sprintf.
The size of the destination buffer is too short.
It doesn't take in consideration of the string terminator.

For example in Rn487xBle::startImmediateAdvertising
char c[2] ;
sprintf(c, "%02X", adType) ;

In my test I got random crashes and not predictable behavior
A simple solution is to increase the size of the buffer.

[SodaqMoja]

@ilcaprone3d indeed that is not good at all.

This code originates from Microchip (as you can see in the copyright notice).
I think it was a mistake to publish it, because it doesn't meet our quality standards.
I am planning to remove this repo. Feel free to fork it while you can.