dt-bindings: iommu: renesas,ipmmu-vmsa: add r8a779f0 support

Document the compatible values for the IPMMU-VMSA blocks in
the Renesas R-Car S4-8 (R8A779F0) SoC and R-Car Gen4.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220208002030.1319984-2-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>