dt-bindings: clock: renesas,cpg-mssr: Document r8a779f0

Add binding documentation for the R-Car S4-8 (R8A779F0) Clock Pulse
Generator.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20211116074130.107554-7-yoshihiro.shimoda.uh@renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

@@ -48,6 +48,7 @@ properties:
       - renesas,r8a77990-cpg-mssr # R-Car E3
       - renesas,r8a77995-cpg-mssr # R-Car D3
       - renesas,r8a779a0-cpg-mssr # R-Car V3U
+      - renesas,r8a779f0-cpg-mssr # R-Car S4-8
 
   reg:
     maxItems: 1