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

Fixes: 1e4854e9 ("drm/amdgpu/powerplay: implement thermal control for tonga.")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(cherry picked from commit 8a0d560f)
Signed-off-by: Alberto Milone <alberto.milone@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>