hw/gpio/pca955*: Move Kconfig switches next to implementations

hw/gpio/pca955*: Move Kconfig switches next to implementations

The move of the Kconfig bits to hw/gpio is fixing a bug in 6328d8ffa6cb9d
("misc/pca955*: Move models under hw/gpio"), which moved the code but forgot to
move the Kconfig sections.

Fixes: 6328d8ffa6cb9d "misc/pca955*: Move models under hw/gpio"
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-id: 20250223114708.1780-4-shentey@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>