Replace GPIO for test "TIMER6" with "P8_10" as TIMERn syntax
is not working on newer kernels such as 4.4.
This is a valid path:
/sys/devices/platform/ocp/ocp:P8_10_pinmux/state
while this path is invalid:
/sys/devices/platform/ocp/ocp:TIMER_pinmux/state
Originally discovered while testing Pull Request #152.
See issue #156 for details.