Unify At91Sam3xPins and At91Sam3uPins into At91SamPins.
Get rid of At91Sam3xSpi and At91Sam3uSpi.
Rename At91Sam3xWatchdog to At91SamWatchdog.
Unify At91Sam3xAdc and At91Sam3uAdc into At91SamAdc.
Mk20Clock: No need to clear CHF in timer unset.
At91Sam3xClock: Port to the new Service design.
At91Sam3uClock: Port to the new Service design.
AvrClock: Port to the new Service design.