drm: Convert atomic drivers from CRTC .disable() to .atomic_disable()

The CRTC .disable() helper operation is deprecated for atomic drivers,
the new .atomic_disable() helper operation being preferred. Convert all
atomic drivers to .atomic_disable() to avoid cargo-cult use of
.disable() in new drivers.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> # for sun4i
Acked-by: Philipp Zabel <p.zabel@pengutronix.de> # for mediatek
Acked-by: Alexey Brodkin <abrodkin@synopsys.com> # for arcpgu
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> # for atmel-hlcdc
Tested-by: Philippe Cornu <philippe.cornu@st.com> # for stm
Acked-by: Philippe Cornu <philippe.cornu@st.com> # for stm
Acked-by: Vincent Abriou <vincent.abriou@st.com> # for sti
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> # for vmwgfx
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170630093646.7928-3-laurent.pinchart+renesas@ideasonboard.com