dt-bindings: display: Intel KeemBay MSSCAM

This patch add bindings for Intel KeemBay MSSCAM syscon

v2: fixed compatible (Sam R.)
Signed-off-by: Anitha Chrisanthus <anitha.chrisanthus@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1604538931-26726-3-git-send-email-anitha.chrisanthus@intel.com

Documentation/devicetree/bindings/display/intel,keembay-msscam.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/intel,keembay-msscam.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Devicetree bindings for Intel Keem Bay MSSCAM
+
+maintainers:
+  - Anitha Chrisanthus <anitha.chrisanthus@intel.com>
+  - Edmond J Dea <edmund.j.dea@intel.com>
+
+description: |
+   MSSCAM controls local clocks in the display subsystem namely LCD clocks and
+   MIPI DSI clocks. It also configures the interconnect between LCD and
+   MIPI DSI.
+
+properties:
+  compatible:
+    items:
+     - const: intel,keembay-msscam
+     - const: syscon
+
+  reg:
+    maxItems: 1
+
+  reg-io-width:
+    const: 4
+
+required:
+  - compatible
+  - reg
+  - reg-io-width
+
+additionalProperties: false
+
+examples:
+  - |
+    msscam:msscam@20910000 {
+        compatible = "intel,keembay-msscam", "syscon";
+        reg = <0x20910000 0x30>;
+        reg-io-width = <4>;
+    };