pinctrl: sh-pfc: r8a7745: Add CAN[01] support

This patch adds PFC CAN0 and CAN1 pin groups and functions, enabling CAN
bus on the RZ/G1E.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>