dt-bindings: clock: Add DT bindings for PLL of Toshiba Visconti TMPV770x SoC

Add device tree bindings for PLL of Toshiba Visconti TMPV770x SoC series.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211025031038.4180686-2-nobuhiro1.iwamatsu@toshiba.co.jpSigned-off-by: Stephen Boyd <sboyd@kernel.org>

Documentation/devicetree/bindings/clock/toshiba,tmpv770x-pipllct.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/toshiba,tmpv770x-pipllct.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Toshiba Visconti5 TMPV770X PLL Controller Device Tree Bindings
+
+maintainers:
+  - Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
+
+description:
+  Toshia Visconti5 PLL controller which supports the PLLs on TMPV770X.
+
+properties:
+  compatible:
+    const: toshiba,tmpv7708-pipllct
+
+  reg:
+    maxItems: 1
+
+  '#clock-cells':
+    const: 1
+
+  clocks:
+    description: External reference clock (OSC2)
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - "#clock-cells"
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+
+    osc2_clk: osc2-clk {
+      compatible = "fixed-clock";
+      clock-frequency = <20000000>;
+      #clock-cells = <0>;
+    };
+
+    soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        pipllct: clock-controller@24220000 {
+            compatible = "toshiba,tmpv7708-pipllct";
+            reg = <0 0x24220000 0 0x820>;
+            #clock-cells = <1>;
+            clocks = <&osc2_clk>;
+        };
+    };
+...