dt-bindings: dma: adi,axi-dmac: deprecate adi,channels node

Deprecate the adi,channels node in the adi,axi-dmac binding. Prior to
IP version 4.3.a, this information was required. Since then, there are
memory-mapped registers that can be read to get the same information.

Acked-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20241216-axi-dma-dt-yaml-v3-2-7b994710c43f@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/dma/adi,axi-dmac.yaml

@@ -33,8 +33,12 @@ properties:
     const: 1
 
   adi,channels:
+    deprecated: true
     type: object
-    description: This sub-node must contain a sub-node for each DMA channel.
+    description:
+      This sub-node must contain a sub-node for each DMA channel. This node is
+      only required for IP versions older than 4.3.a and should otherwise be
+      omitted.
     additionalProperties: false
 
     properties:
@@ -113,7 +117,6 @@ required:
   - interrupts
   - clocks
   - "#dma-cells"
-  - adi,channels
 
 examples:
   - |
@@ -123,17 +126,4 @@ examples:
         interrupts = <0 57 0>;
         clocks = <&clkc 16>;
         #dma-cells = <1>;
-
-        adi,channels {
-            #size-cells = <0>;
-            #address-cells = <1>;
-
-            dma-channel@0 {
-                reg = <0>;
-                adi,source-bus-width = <32>;
-                adi,source-bus-type = <0>; /* Memory mapped */
-                adi,destination-bus-width = <64>;
-                adi,destination-bus-type = <2>; /* FIFO */
-            };
-        };
     };