platform/x86: panasonic-laptop: Resolve hotkey double trigger bug

Sometimes double ACPI events are triggered for brightness, vol and mute
hotkeys. This patch fixes it.

Signed-off-by: Kenneth Chan <kenneth.t.chan@gmail.com>
Link: https://lore.kernel.org/r/20200821181433.17653-8-kenneth.t.chan@gmail.com


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