drivers: led_strip: ws2812_rpi_pico_pio: Change output-pin to gpios

For sharing pin definition property with `worldsemi,ws2812-gpio`,
rename `output-pin` to `gpios`.

Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>

dts/bindings/led_strip/worldsemi,ws2812-gpio.yaml

@@ -11,12 +11,4 @@ description: |
 
 compatible: "worldsemi,ws2812-gpio"
 
-include: [base.yaml, ws2812.yaml]
-
-properties:
-  gpios:
-    type: phandle-array
-    required: true
-    description: |
-      GPIO phandle and specifier for the pin connected to the daisy
-      chain's input pin. Exactly one pin should be given.
+include: [base.yaml, ws2812-gpio.yaml]

dts/bindings/led_strip/worldsemi,ws2812-rpi_pico-pio.yaml

@@ -47,18 +47,16 @@ child-binding:
     Worldsemi WS2812 or compatible LED strip driver based on RaspberryPi Pico's PIO
     The LED strip node can put up to 4 instances under a single PIO node.
 
-  include: ws2812.yaml
+  include: ws2812-gpio.yaml
 
   properties:
-    output-pin:
-      type: int
-      required: true
+    gpios:
       description: |
-        Select the output pin.
+        Inherited from ws2812-gpio.yaml.
 
         Note: This driver does not configure the output pin.
         You need to configure the pin with pinctrl that is in the parent node configuration
-        for use by PIO.
+        for use by PIO. This property only uses the GPIO pin number and ignores flags.
 
     frequency:
       type: int

dts/bindings/led_strip/ws2812-gpio.yaml

@@ -0,0 +1,15 @@
+# Copyright (c) 2024, TOKITA Hiroshi
+# SPDX-License-Identifier: Apache-2.0
+
+include: ws2812.yaml
+
+description: |
+  Common definition GPIO based WS2812 node
+
+properties:
+  gpios:
+    type: phandle-array
+    required: true
+    description: |
+      GPIO phandle and specifier for the pin connected to the
+      led-strip. Exactly one pin should be given.