Current adoption on top of nrfx only reads the GPIO->IN register.
In order to read back an output state, nrf_gpio_pin_out_read has
to be called.
This patch concatinate the two read functions such that, if
either IN or OUT register has a value 1 it will return this,
else 0.
Updating lib/nrfx submodule to latest version of master to get
the new GPIO API to read pin direction.
(nrfx: d37b16f2b894b0928395f6f56ca741287a31a244)
b7ce2f1460