spi: dt-bindings: renesas,rzv2h-rspi: Document RZ/G3L SoC

Document RSPI IP found on the RZ/G3L SoC. The RSPI IP is compatible with
the RZ/V2H RSPI IP, but has 2 clocks compared to 3 on RZ/V2H.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://patch.msgid.link/20260408085418.18770-2-biju.das.jz@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/renesas,rzv2h-rspi.yaml

@@ -13,6 +13,7 @@ properties:
   compatible:
     oneOf:
       - enum:
+          - renesas,r9a08g046-rspi # RZ/G3L
           - renesas,r9a09g057-rspi # RZ/V2H(P)
           - renesas,r9a09g077-rspi # RZ/T2H
       - items:
@@ -81,6 +82,34 @@ required:
 
 allOf:
   - $ref: spi-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - renesas,r9a08g046-rspi
+    then:
+      properties:
+        clocks:
+          maxItems: 2
+
+        clock-names:
+          items:
+            - const: pclk
+            - const: tclk
+
+        dmas:
+          maxItems: 2
+
+        dma-names:
+          items:
+            - const: rx
+            - const: tx
+
+      required:
+        - resets
+        - reset-names
+
   - if:
       properties:
         compatible: