pinctrl: renesas: r8a77470: Reduce size for narrow VIN1 channel

pinctrl: renesas: r8a77470: Reduce size for narrow VIN1 channel

The second video-in channel on RZ/G1C has only 12 data lanes, but the
pin control driver uses the vin_data union, which is meant for 24 data
lanes, thus wasting space.

Fix this by using the vin_data12 union instead.

This reduces kernel size by 96 bytes.

Fixes: 50f3f2d73e3426ba ("pinctrl: sh-pfc: Reduce kernel size for narrow VIN channels")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/52716fa89139f6f92592633edb52804d4c5e18f0.1640269757.git.geert+renesas@glider.be