arm64: dts: rename grf-gpio nodename in rk3328.dtsi

A test with the command below gives this error:

/arch/arm64/boot/dts/rockchip/rk3328-a1.dt.yaml: syscon@ff100000:
grf-gpio: {'compatible': ['rockchip,rk3328-grf-gpio'],
'gpio-controller': True, '#gpio-cells': [[2]], 'phandle': [[68]]} is not
of type 'array'

Due to the regex "(?<!,nr)-gpios?$" anything that ends on
'-gpio', '-gpios' gives a match.

Rename 'grf-gpio' nodename to generic 'gpio'

make ARCH=arm64 dtbs_check
DT_SCHEMA_FILES=~/.local/lib/python3.5/site-packages/dtschema/
schemas/gpio/gpio-consumer.yaml
Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Link: https://lore.kernel.org/r/20210512122346.9463-5-jbx6244@gmail.comSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3328.dtsi

@@ -288,7 +288,7 @@ io_domains: io-domains {
 			status = "disabled";
 		};
 
-		grf_gpio: grf-gpio {
+		grf_gpio: gpio {
 			compatible = "rockchip,rk3328-grf-gpio";
 			gpio-controller;
 			#gpio-cells = <2>;