Add build.board property

This causes the ARDUINO_PINOCCIO macro to be defined when the Pinoccio
boards are selected. This does not distinguish between the 256RFR2 and
128RFR2 versions, but since the later was only a prototype, and the
regular CPU defines are also available, this shouldn't be a problem (the
alternative would be to check for both boards everywhere in the code,
which isn't nice either).

Author: matthijskooijman

hardware/pinoccio/avr/boards.txt

@@ -20,6 +20,7 @@ pinoccio.build.mcu=atmega256rfr2
 pinoccio.build.f_cpu=16000000L
 pinoccio.build.core=arduino
 pinoccio.build.variant=pinoccio
+pinoccio.build.board=PINOCCIO
 
 ##############################################################
 pinoccio128.name=Pinoccio 128RFA1
@@ -43,3 +44,4 @@ pinoccio128.build.mcu=atmega128rfa1
 pinoccio128.build.f_cpu=16000000L
 pinoccio128.build.core=pinoccio
 pinoccio128.build.variant=pinoccio
+pinoccio.build.board=PINOCCIO