platform/x86: dell-wmi: Add WMI event 0x0012 0x0003 to the list

It looks like that on Dell Latitude E6440 is WMI event 0x0012 0x0003 sent
when display changes brightness. When it happens kernel prints
"dell_wmi: Unknown WMI event type 0x12" message into dmesg.

So ignore it for now to not spam dmesg.

Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220827133040.15932-1-pali@kernel.org


Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>