platform/x86: wmi: Fix error handling in legacy WMI notify handler functions

platform/x86: wmi: Fix error handling in legacy WMI notify handler functions

When wmi_install_notify_handler()/wmi_remove_notify_handler() are
unable to enable/disable the WMI device, they unconditionally return
an error to the caller.
When registering legacy WMI notify handlers, this means that the
callback remains registered despite wmi_install_notify_handler()
having returned an error.
When removing legacy WMI notify handlers, this means that the
callback is removed despite wmi_remove_notify_handler() having
returned an error.

Fix this by only warning when the WMI device could not be enabled.
This behaviour matches the bus-based WMI interface.

Tested on a Dell Inspiron 3505 and a Acer Aspire E1-731.

Fixes: 58f6425eb92f ("WMI: Cater for multiple events with same GUID")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20240103192707.115512-2-W_Armin@gmx.de
Signed-off-by: Hans de Goede <hdegoede@redhat.com>