pinctrl: renesas: r8a7792: Share SDHI pin group data

Pin group sdhi0_data1 is a subset of sdhi0_data4.

This reduces kernel size by 8 bytes.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/76a245f8b39f8e71e3311868ec15ce8c9c44bde0.1640269757.git.geert+renesas@glider.be