ARM: dts: sunxi: add support for NetCube Systems Nagami Keypad Carrier

ARM: dts: sunxi: add support for NetCube Systems Nagami Keypad Carrier

The NetCube Systems Nagami Keypad Carrier uses the Nagami SoM and contains
a TCA8418 connected to a 4x4 matrix keypad. The I2C2 interface is connected
to said TCA8418 and also a header for an PN532 NFC-Module. It also provides
a pin-header for a bi-color status led. Ethernet with PoE support is
available on a screwterminal after magnetics.

Signed-off-by: Lukas Schmid <lukas.schmid@netcube.li>
Link: https://patch.msgid.link/20250831162536.2380589-6-lukas.schmid@netcube.li
[wens@csie.org: fix indentation for board level compatible fallback,
		gpio-line-names and keypad matrix.]
Signed-off-by: Chen-Yu Tsai <wens@csie.org>