drivers: misc: Add driver for RaspberryPi Pico PIO

Added a generic driver for RaspberryPi Pico PIO.
This driver is an intermediate driver for abstracting the PIO
device driver from physical pin configuration.

Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@fujitsu.com>
Signed-off-by: Yonatan Schachter <yonatan.schachter@gmail.com>
Signed-off-by: Ionut Catalin Pavel <iocapa@iocapa.com>