dts: bindings: clean up redundant required false attributes

DTS property attributes are (by default) not required.

Explicitly specifying `required: false` is redundant.
Perhaps a warning to that effect would be useful.

Signed-off-by: Chris Friedt <cfriedt@meta.com>

dts/bindings/kscan/focaltech,ft5336.yaml

@@ -10,4 +10,3 @@ include: [kscan.yaml, i2c-device.yaml]
 properties:
     int-gpios:
       type: phandle-array
-      required: false

dts/bindings/kscan/goodix,gt911.yaml

@@ -10,7 +10,5 @@ include: [kscan.yaml, i2c-device.yaml]
 properties:
     irq-gpios:
       type: phandle-array
-      required: false
     reset-gpios:
       type: phandle-array
-      required: false

dts/bindings/kscan/hynitron,cst816s.yaml

@@ -10,7 +10,6 @@ include: i2c-device.yaml
 properties:
     irq-gpios:
       type: phandle-array
-      required: false
       description: |
         The irq signal defaults to active low as produced by the
         sensor. The property value should ensure the flags properly
@@ -18,7 +17,6 @@ properties:
 
     rst-gpios:
       type: phandle-array
-      required: false
       description: |
         The reset signal defaults to active low to the
         sensor. The property value should ensure the flags properly

dts/bindings/kscan/microchip,cap1203.yaml

@@ -10,4 +10,3 @@ include: [kscan.yaml, i2c-device.yaml]
 properties:
     int-gpios:
       type: phandle-array
-      required: false

dts/bindings/kscan/microchip,xec-kscan.yaml

@@ -18,12 +18,6 @@ properties:
     reg:
       required: true
 
-    pinctrl-0:
-      required: false
-
-    pinctrl-names:
-      required: false
-
     interrupts:
       required: true