dt-bindings: dmaengine: sprd: deprecate '#dma-channels'

The generic property, used in most of the drivers and defined in generic
dma-common DT bindings, is 'dma-channels'.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220503065147.51728-2-krzysztof.kozlowski@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/dma/sprd-dma.txt

@@ -8,10 +8,13 @@ Required properties:
 - interrupts: Should contain one interrupt shared by all channel.
 - #dma-cells: must be <1>. Used to represent the number of integer
 	cells in the dmas property of client device.
-- #dma-channels : Number of DMA channels supported. Should be 32.
+- dma-channels : Number of DMA channels supported. Should be 32.
 - clock-names: Should contain the clock of the DMA controller.
 - clocks: Should contain a clock specifier for each entry in clock-names.
 
+Deprecated properties:
+- #dma-channels : Number of DMA channels supported. Should be 32.
+
 Example:
 
 Controller:
@@ -20,7 +23,7 @@ apdma: dma-controller@20100000 {
 	reg = <0x20100000 0x4000>;
 	interrupts = <GIC_SPI 50 IRQ_TYPE_LEVEL_HIGH>;
 	#dma-cells = <1>;
-	#dma-channels = <32>;
+	dma-channels = <32>;
 	clock-names = "enable";
 	clocks = <&clk_ap_ahb_gates 5>;
 };