pinctrl: renesas: Allow up to 10 fields for drive_regs

Needed to support R-Car E3 and RZ/G2E drive regs.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220320092542.2308-2-wsa+renesas@sang-engineering.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>