dt-bindings: mtd: convert nxp-spifi.txt to yaml format

Convert nxp-spifi.txt to yaml format.

Additional changes:
- ref /schemas/spi/spi-controller.yaml.
- remove label in example.
- change node name to spi in example.
- remove child node in example.

Signed-off-by: Frank Li <[email protected]>
Reviewed-by: Rob Herring (Arm) <[email protected]>
Signed-off-by: Miquel Raynal <[email protected]>

Author: nxpfrankli

Documentation/devicetree/bindings/mtd/nxp,lpc1773-spifi.yaml

@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/nxp,lpc1773-spifi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP SPI Flash Interface (SPIFI)
+
+description:
+  NXP SPIFI is a specialized SPI interface for serial Flash devices.
+  It supports one Flash device with 1-, 2- and 4-bits width in SPI
+  mode 0 or 3. The controller operates in either command or memory
+  mode. In memory mode the Flash is accessible from the CPU as
+  normal memory.
+
+maintainers:
+  - Frank Li <[email protected]>
+
+properties:
+  compatible:
+    const: nxp,lpc1773-spifi
+
+  reg:
+    maxItems: 2
+
+  reg-names:
+    items:
+      - const: spifi
+      - const: flash
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 2
+
+  clock-names:
+    items:
+      - const: spifi
+      - const: reg
+
+  resets:
+    maxItems: 1
+
+  spi-cpol:
+    enum: [0, 3]
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - interrupts
+  - clocks
+  - clock-names
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/lpc18xx-ccu.h>
+
+    spi@40003000 {
+        compatible = "nxp,lpc1773-spifi";
+        reg = <0x40003000 0x1000>, <0x14000000 0x4000000>;
+        reg-names = "spifi", "flash";
+        interrupts = <30>;
+        clocks = <&ccu1 CLK_SPIFI>, <&ccu1 CLK_CPU_SPIFI>;
+        clock-names = "spifi", "reg";
+        resets = <&rgu 53>;
+    };
+