After installing that and compiling, it gave a couple of warnings
/boot/dtb/overlay/sun8i-h3-gpio-keys.dtbo: Warning (unit_address_vs_reg): /fragment@1/__overlay__/mykeypad/button@10: node has a unit name, but no reg property
/boot/dtb/overlay/sun8i-h3-gpio-keys.dtbo: Warning (avoid_unnecessary_addr_size): /fragment@1/__overlay__/mykeypad: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property
Is that okay