I noticed that this code was referring to samd-specific functionality,
and isn't enabled except in one samd board (pewpew10). Move it.
There is incomplte support for _pew in mimxrt10xx which then caused build
errors; adding a #if guard to check for _pew being enabled fixes it.
The _pew module is not likely to be important on mimxrt but I'll leave the
choice to remove it to someone else.
This gets all the purely internal references. Some uses of
protomatter/Protomatter/PROTOMATTER remain, as they are references
to symbols in the Protomatter C library itself.
