dt-bindings: soc: ti: pruss: Add documentation for PA_STATS support

Add documentation for pa-stats node which is syscon regmap for
PA_STATS registers. This will be used to dump statistics maintained by
ICSSG firmware.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Link: https://patch.msgid.link/20240822122652.1071801-2-danishanwar@ti.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/devicetree/bindings/soc/ti/ti,pruss.yaml

@@ -278,6 +278,26 @@ patternProperties:
 
     additionalProperties: false
 
+  ^pa-stats@[a-f0-9]+$:
+    description: |
+      PA-STATS sub-module represented as a SysCon. PA_STATS is a set of
+      registers where different statistics related to ICSSG, are dumped by
+      ICSSG firmware. This syscon sub-module will help the device to
+      access/read/write those statistics.
+
+    type: object
+
+    additionalProperties: false
+
+    properties:
+      compatible:
+        items:
+          - const: ti,pruss-pa-st
+          - const: syscon
+
+      reg:
+        maxItems: 1
+
   interrupt-controller@[a-f0-9]+$:
     description: |
       PRUSS INTC Node. Each PRUSS has a single interrupt controller instance