pinctrl: sh-pfc: r8a7791: Add R8A7743 support

Renesas RZ/G1M (R8A7743) is pin compatible with R-Car M2-W/N (R8A7791/3),
however it doesn't have several automotive specific peripherals.  Annotate
all the items that only exist on the R-Car SoCs and only supply the pin
groups/functions existing on a given SoC...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>
[geert: Drop annotations, as they are implied by pin groups/functions]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>