BugLink: http://bugs.launchpad.net/bugs/1553179

commit dbb17a21 upstream.

Need to call this on resume if displays changes during
suspend in order to properly be notified of changes.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>