Remove the unnecessary #address-cells/#size-cells to avoid warnings
from W=1 build like this:

arch/arm/boot/dts/imx6qdl-gw52xx.dtsi:33.12-78.4: Warning (avoid_unnecessary_addr_size): /gpio-keys: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
[fabio: Make the warning messages more succint]
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>