pinctrl: meson: support gpio toggle command

pinctrl: meson: support gpio toggle command

meson_gpio_get() always assumes gpio is configured to input mode. This
is incorrect and breaks `gpio toggle` command:

gpio: pin aobus-banks2 (gpio 2) value is 0
   Warning: value of pin is still 1

Fix it by adding the logic to handle both input and output mode.

Fixes: 2009a8d03fe5 ("pinctrl: meson: add GPIO support")
Signed-off-by: Yang Xiwen <forbidden405@outlook.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250617-meson_ppinctrl-v3-1-218d9321a8d2@outlook.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>