dt-bindings: sram: qcom,imem: Allow modem-tables subnode

The IP Accelerator hardware/firmware owns a sizeable region within the
IMEM, named 'modem-tables', containing various packet processing
configuration data.

It's not actually accessed by the OS, although we have to IOMMU-map it
with the IPA device, so that presumably the firmware can act upon it.

Allow it as a subnode of IMEM.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Alex Elder <elder@riscstar.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://patch.msgid.link/20260302-topic-ipa_imem-v6-1-c0ebbf3eae9f@oss.qualcomm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/devicetree/bindings/sram/qcom,imem.yaml

@@ -67,6 +67,20 @@ properties:
     $ref: /schemas/power/reset/syscon-reboot-mode.yaml#
 
 patternProperties:
+  "^modem-tables@[0-9a-f]+$":
+    type: object
+    description:
+      Region containing packet processing configuration for the IP Accelerator.
+
+    properties:
+      reg:
+        maxItems: 1
+
+    required:
+      - reg
+
+    additionalProperties: false
+
   "^pil-reloc@[0-9a-f]+$":
     $ref: /schemas/remoteproc/qcom,pil-info.yaml#
     description: Peripheral image loader relocation region