That seems to be a makefile issue. I don't know much at all about the P1 platform, so my only advice is to go into the firmware directory, and re-get the firmware from github (See below). If that doesn't work, I'm at a bit of a loss, and would have to direct you towards someone with more knowledge about the P1 firmware.
CAUTION!!!!: If you have modified any files, such as application.cpp, or added anything to the firmware directory, THIS COMMAND WILL DELETE IT! With that in mind, you can issue this to reset the firmware to the latest branch:
git reset --hard origin\latest