include: zephyr: dt-bindings: gpio: Add `arduino-nano-header` defines

To make the pin names of the Arduino Nano header easier to understand,
we will introduce a macro definition for the pin names.

And also update the definition of `nano_33_ble`, `nano_33_iot`,
`nucleo_g031k8`, and `nucleo_l031k6` with the definitions.

Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>