power: supply: collie: Fix wakeup source leaks on device unbind

Device can be unbound, so driver must also release memory for the wakeup
source.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250406202730.55096-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>