gpio: regmap: fix memory leak of gpio_regmap structure

gpio: regmap: fix memory leak of gpio_regmap structure

The gpio_regmap structure is leaked on the error path. Fix this by
jumping to the appropriate kfree instead of returning directly.

Fixes: db305161880a ("gpio: regmap: Allow ngpio to be read from the property")
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Suggested-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/20250922142427.3310221-7-ioana.ciornei@nxp.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>