pinctrl: meson: a4: remove special data processing

According to the data specifications of Amlogic's existing SoCs,
the function register offset and the bit offset are the same
value among various chips. Therefore, general processing can
be carried out without the need for private data modification.
Drop special data processing.

Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Link: https://lore.kernel.org/20250527-s6-s7-pinctrl-v3-2-44f6a0451519@amlogic.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>