dt-bindings: display: himax-hx8394: remove reset-gpio from required properties

Remove "reset-gpio" property from required properties list and
make it optional.When interfaced with some boards where reset line is not
populated it leads to driver probe issues.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
Acked-by: Hari Prasath Gujulan Elango <hari.prasathge@microchip.com>

Author: manikandan-m11

Documentation/devicetree/bindings/display/panel/himax,hx8394.yaml

@@ -42,7 +42,6 @@ properties:
 required:
   - compatible
   - reg
-  - reset-gpios
   - backlight
   - port
   - vcc-supply