pinctrl: renesas: Implement unlock register masks

The V3U SoC has several unlock registers, one per register group. They
reside at offset zero in each 0x200 bytes-sized block.

To avoid adding yet another table to the PFC implementation, this
patch adds the option to specify an address mask instead of the fixed
address in sh_pfc_soc_info::unlock_reg.

Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210112165912.30876-2-uli+renesas@fpond.eu


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