power: Add optional keyboard-side-buttons udev rules file.

Add a new udev/optional directory containing a
92-powerd-tags-keyboard-side-buttons.rules file that can be
selectively installed by the power_manager ebuild for
convertible devices that need to avoid inhibiting the
internal keyboard while in tablet mode due to side
power/volume button events being routed through it.

BUG=chromium:703691,chromium:708180
TEST=none

Change-Id: I06ff6e1c8c291ea68f7315afdda5426ac5fcf33c
Reviewed-on: https://chromium-review.googlesource.com/469251
Commit-Ready: Dan Erat <derat@chromium.org>
Tested-by: Dan Erat <derat@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
(cherry picked from commit 156511c9c6893200783d439ff7b1ebf1a27dc9d5)
Reviewed-on: https://chromium-review.googlesource.com/472530
1 file changed