dt: bindings: add new DT entry for ath11k PCI device support

Ath11k driver supports PCI devices such as QCN9074/QCA6390.
Ath11k firmware uses host DDR memory, DT entry is used to
reserve host DDR memory regions, send these memory base
addresses using DT entries.
Signed-off-by: Anilkumar Kolli <akolli@codeaurora.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/1638789319-2950-1-git-send-email-akolli@codeaurora.org

Documentation/devicetree/bindings/net/wireless/qcom,ath11k.yaml

@@ -150,6 +150,12 @@ properties:
       string to uniquely identify variant of the calibration data in the
       board-2.bin for designs with colliding bus and device specific ids
 
+  memory-region:
+    maxItems: 1
+    description:
+      phandle to a node describing reserved memory (System RAM memory)
+      used by ath11k firmware (see bindings/reserved-memory/reserved-memory.txt)
+
 required:
   - compatible
   - reg
@@ -279,3 +285,27 @@ examples:
                           "tcl2host-status-ring";
         qcom,rproc = <&q6v5_wcss>;
     };
+
+  - |
+
+    reserved-memory {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        qcn9074_0: qcn9074_0@51100000 {
+            no-map;
+            reg = <0x0 0x51100000 0x0 0x03500000>;
+        };
+    };
+
+    pci {
+        pcie0 {
+            #size-cells = <2>;
+            #address-cells = <3>;
+ 
+            wifi_0: wifi@0 {
+                reg = <0 0 0 0 0>;
+                memory-region = <&qcn9074_0>;
+            };
+        };
+    };