spi: support hclk

this patch support hclk for AHB bus.
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220321013922.24067-3-leilk.liu@mediatek.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/mediatek,spi-mt65xx.yaml

@@ -53,16 +53,20 @@ properties:
     maxItems: 1
 
   clocks:
+    minItems: 3
     items:
       - description: clock used for the parent clock
       - description: clock used for the muxes clock
       - description: clock used for the clock gate
+      - description: clock used for the AHB bus, this clock is optional
 
   clock-names:
+    minItems: 3
     items:
       - const: parent-clk
       - const: sel-clk
       - const: spi-clk
+      - const: hclk
 
   mediatek,pad-select:
     $ref: /schemas/types.yaml#/definitions/uint32-array