dt-bindings: riscv: Require block-size for Zicbom, Zicbop, and Zicboz

Zicbom, Zicbop, and Zicboz have no default cache block size, so a
devicetree that declares one must also provide the matching
riscv,cbom/cbop/cboz-block-size property. Make it required so a
missing block-size property can be caught by dtbs_check.

Match only nodes that use riscv,isa-extensions, so nodes carrying just
the deprecated riscv,isa string are not affected.

Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Guodong Xu <guodong.xu@oss.qualcomm.com>
Link: https://patch.msgid.link/20260920-rva23u64-hwprobe-v2-v8-2-5f14bc5c23d3@oss.qualcomm.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Documentation/devicetree/bindings/riscv/extensions.yaml

@@ -1211,6 +1211,38 @@ allOf:
           not:
             contains:
               const: zilsd
+  # All three Zicbo* extensions require their block size property as there's no
+  # default.
+  - if:
+      properties:
+        riscv,isa-extensions:
+          contains:
+            const: zicbom
+      required:
+        - riscv,isa-extensions
+    then:
+      required:
+        - riscv,cbom-block-size
+  - if:
+      properties:
+        riscv,isa-extensions:
+          contains:
+            const: zicbop
+      required:
+        - riscv,isa-extensions
+    then:
+      required:
+        - riscv,cbop-block-size
+  - if:
+      properties:
+        riscv,isa-extensions:
+          contains:
+            const: zicboz
+      required:
+        - riscv,isa-extensions
+    then:
+      required:
+        - riscv,cboz-block-size
 
 additionalProperties: true
 ...