ARM: dts: rockchip: Fix LED node names on rk3288-phycore-rdk

According to nxp,pca953x.yaml, the pattern for the led names should be:
 "^led-[0-9a-z]+$".

Change it accordingly to fix the following dt-schema warning"

leddimmer@62 (nxp,pca9533): 'led1', 'led2', 'led3', 'led4' do not match any
of the regexes: '^led-[0-9a-z]+$', '^pinctrl-[0-9]+$'

Signed-off-by: Fabio Estevam <festevam@nabladev.com>
Link: https://patch.msgid.link/20260311135604.21634-1-festevam@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Author: Fabio Estevam

arch/arm/boot/dts/rockchip/rk3288-phycore-rdk.dts

@@ -125,25 +125,25 @@
 		compatible = "nxp,pca9533";
 		reg = <0x62>;
 
-		led1 {
+		led-1 {
 			label = "red:user1";
 			linux,default-trigger = "none";
 			type = <PCA9532_TYPE_LED>;
 		};
 
-		led2 {
+		led-2 {
 			label = "green:user2";
 			linux,default-trigger = "none";
 			type = <PCA9532_TYPE_LED>;
 		};
 
-		led3 {
+		led-3 {
 			label = "blue:user3";
 			linux,default-trigger = "none";
 			type = <PCA9532_TYPE_LED>;
 		};
 
-		led4 {
+		led-4 {
 			label = "red:user4";
 			linux,default-trigger = "none";
 			type = <PCA9532_TYPE_LED>;