clk: renesas: cpg-mssr: Document r8a7796 support

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Simon Horman <horms+renesas@verge.net.au>

Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt

@@ -13,7 +13,8 @@ They provide the following functionalities:
 
 Required Properties:
   - compatible: Must be one of:
-      - "renesas,r8a7795-cpg-mssr" for the r8a7795 SoC
+      - "renesas,r8a7795-cpg-mssr" for the r8a7795 SoC (R-Car H3)
+      - "renesas,r8a7796-cpg-mssr" for the r8a7796 SoC (R-Car M3-W)
 
   - reg: Base address and length of the memory resource used by the CPG/MSSR
     block
@@ -21,8 +22,8 @@ Required Properties:
   - clocks: References to external parent clocks, one entry for each entry in
     clock-names
   - clock-names: List of external parent clock names. Valid names are:
-      - "extal" (r8a7795)
-      - "extalr" (r8a7795)
+      - "extal" (r8a7795, r8a7796)
+      - "extalr" (r8a7795, r8a7796)
 
   - #clock-cells: Must be 2
       - For CPG core clocks, the two clock specifier cells must be "CPG_CORE"