ARM: dts: vt8500: align panel timings node name with dtschema

DT schema expects panel timings node to follow certain pattern,
dtbs_check warnings:

  vt8500-bv07.dtb: display-timings: '800x480' does not match any of the regexes: '^timing', 'pinctrl-[0-9]+'

Linux drivers do not care about node name, so this should not have
effect on Linux.

Link: https://lore.kernel.org/r/20240509104749.216605-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

arch/arm/boot/dts/vt8500/vt8500-bv07.dts

@@ -16,7 +16,7 @@
 	bits-per-pixel = <16>;
 	display-timings {
 		native-mode = <&timing0>;
-		timing0: 800x480 {
+		timing0: timing-800x480 {
 			clock-frequency = <0>; /* unused but required */
 			hactive = <800>;
 			vactive = <480>;

arch/arm/boot/dts/vt8500/wm8505-ref.dts

@@ -16,7 +16,7 @@
 	bits-per-pixel = <32>;
 	display-timings {
 		native-mode = <&timing0>;
-		timing0: 800x480 {
+		timing0: timing-800x480 {
 			clock-frequency = <0>; /* unused but required */
 			hactive = <800>;
 			vactive = <480>;

arch/arm/boot/dts/vt8500/wm8650-mid.dts

@@ -17,7 +17,7 @@
 
 	display-timings {
 		native-mode = <&timing0>;
-		timing0: 800x480 {
+		timing0: timing-800x480 {
 			clock-frequency = <0>; /* unused but required */
 			hactive = <800>;
 			vactive = <480>;

arch/arm/boot/dts/vt8500/wm8850-w70v2.dts

@@ -28,7 +28,7 @@
 	bits-per-pixel = <16>;
 	display-timings {
 		native-mode = <&timing0>;
-		timing0: 800x480 {
+		timing0: timing-800x480 {
 			clock-frequency = <0>; /* unused but required */
 			hactive = <800>;
 			vactive = <480>;