BugLink: http://bugs.launchpad.net/bugs/1546572

Add required structures for amd_powerplay_display_configuration_change
Signed-off-by: Eric Yang <eric.yang2@amd.com>
(cherry picked from commit 14f63411)
Signed-off-by: Alberto Milone <alberto.milone@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>