power: supply: qcom_pmi8998_charger: fix wakeirq

Unloading and reloading the driver (e.g. when built as a module)
currently leads to errors trying to enable wake IRQ since it's already
enabled.

Use devm to manage this for us so it correctly gets disabled when
removing the driver.

Additionally, call device_init_wakeup() so that charger attach/remove
will trigger a wakeup by default.

Fixes: 8648aeb5 ("power: supply: add Qualcomm PMI8998 SMB2 Charger driver")
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250619-smb2-smb5-support-v1-3-ac5dec51b6e1@linaro.org


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