pinctrl: samsung: Finish initializing the gpios before registering them

As soon as a gpio is registered, it should be usable by a consumer. So,
do all the initialization before registering the gpios. Without this
change, a consumer can request a GPIO IRQ and have the gpio to IRQ
mapping fail.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Chanho Park <chanho61.park@samsung.com>
Tested-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220727013349.3056826-1-saravanak@google.com