dt-bindings: display: panel: add Ilitek ili9806e panel controller

Add the device tree binding for the Ilitek ILI9806E controller which can
be found on the Ortustech COME35H3P70ULC DSI display panel.

There are no peculiarities except for two different power signals.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/20240626144433.3097793-2-mwalle@kernel.orgSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240626144433.3097793-2-mwalle@kernel.org

Documentation/devicetree/bindings/display/panel/ilitek,ili9806e.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/ilitek,ili9806e.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ilitek ILI9806E based MIPI-DSI panels
+
+maintainers:
+  - Michael Walle <mwalle@kernel.org>
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - ortustech,com35h3p70ulc
+      - const: ilitek,ili9806e
+
+  reg:
+    maxItems: 1
+
+  vdd-supply: true
+  vccio-supply: true
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+  - vccio-supply
+  - reset-gpios
+  - backlight
+  - port
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "ortustech,com35h3p70ulc", "ilitek,ili9806e";
+            reg = <0>;
+            vdd-supply = <&reg_vdd_panel>;
+            vccio-supply = <&reg_vccio_panel>;
+            reset-gpios = <&gpio3 6 GPIO_ACTIVE_LOW>;
+            backlight = <&backlight>;
+
+            port {
+                panel_in: endpoint {
+                    remote-endpoint = <&dsi_out>;
+                };
+            };
+        };
+    };
+
+...