mraa-gpio: Fix commands should not be in main
mraa-gpio: Fix commands should not be in main

This seems to work with microkernel but causes issues in nanokernel, it's
obviously wrong so it's a good fix reguardless :)

Signed-off-by: Brendan Le Foll <3e0e8c4069934e8b47d99704927a85c66c0ceb33@intel.com>

jontrulson/zmraa,malikabhi05/zmraa-1,whbruce/zmraa,intel-iot-devkit/zmraa