mraa: add mraa-gpio tool
mraa: add mraa-gpio tool

Signed-off-by: Brendan Le Foll <3e0e8c4069934e8b47d99704927a85c66c0ceb33@intel.com>
(cherry picked from commit b51ed49722029d07d48b2bba1c0c58c008930af9)

gizero/meta-intel-iot-middleware