dt-bindings: fpga: Convert lattice,ice40-fpga-mgr to DT schema

Convert the lattice,ice40-fpga-mgr binding to DT schema format. It's a
straight-forward conversion.

Link: https://patch.msgid.link/20251029185503.2124434-1-robh@kernel.org
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

Author: robherring

Documentation/devicetree/bindings/fpga/lattice,ice40-fpga-mgr.yaml

@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fpga/lattice,ice40-fpga-mgr.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lattice iCE40 FPGA Manager
+
+maintainers:
+  - Joel Holdsworth <joel@airwebreathe.org.uk>
+
+properties:
+  compatible:
+    const: lattice,ice40-fpga-mgr
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    minimum: 1000000
+    maximum: 25000000
+
+  cdone-gpios:
+    maxItems: 1
+    description: GPIO input connected to CDONE pin
+
+  reset-gpios:
+    maxItems: 1
+    description:
+      Active-low GPIO output connected to CRESET_B pin. Note that unless the
+      GPIO is held low during startup, the FPGA will enter Master SPI mode and
+      drive SCK with a clock signal potentially jamming other devices on the bus
+      until the firmware is loaded.
+
+required:
+  - compatible
+  - reg
+  - spi-max-frequency
+  - cdone-gpios
+  - reset-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        fpga@0 {
+            compatible = "lattice,ice40-fpga-mgr";
+            reg = <0>;
+            spi-max-frequency = <1000000>;
+            cdone-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>;
+            reset-gpios = <&gpio 22 GPIO_ACTIVE_LOW>;
+        };
+    };