dt-bindings: net: airoha: Add EN7581 memory-region property

Introduce memory-region and memory-region-names properties for the
ethernet node available on EN7581 SoC in order to reserve system memory
for hw forwarding buffers queue used by the QDMA modules.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20250521-airopha-desc-sram-v3-1-a6e9b085b4f0@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Documentation/devicetree/bindings/net/airoha,en7581-eth.yaml

@@ -57,6 +57,16 @@ properties:
       - const: hsi-mac
       - const: xfp-mac
 
+  memory-region:
+    items:
+      - description: QDMA0 buffer memory
+      - description: QDMA1 buffer memory
+
+  memory-region-names:
+    items:
+      - const: qdma0-buf
+      - const: qdma1-buf
+
   "#address-cells":
     const: 1
 
@@ -140,6 +150,9 @@ examples:
                      <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>,
                      <GIC_SPI 64 IRQ_TYPE_LEVEL_HIGH>;
 
+        memory-region = <&qdma0_buf>, <&qdma1_buf>;
+        memory-region-names = "qdma0-buf", "qdma1-buf";
+
         airoha,npu = <&npu>;
 
         #address-cells = <1>;