The file always exist so no need to do '-include'.
Replaced using:
sed -i 's|-\(include $(RIOTCPU)/.*/Makefile.features\)|\1|' \
$(git grep -l '$(RIOTCPU)/.*/Makefile.features' boards)
Uno and Duemilanove(atmega328p version) are nearly the same boards.
The only difference is that the Duemilanove use an FTDI usb chip,
while the Uno use an Atmel which acts as USB/Serial converter.
All of the code needed to support these boards is in arduino-common.