The PIO cores on Altera Nios-II processors can be used
for GPIOs and each PIO core can be configured as Input only,
Output only or as Bidirectional port from the Qsys tool.
The present Nios-II softcpu image on the Zephyr only has the
support for Output only port and the PIOs[0:3] are wired to
LED[0:3] on the Altera MAX10 board.
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>