drm/omap: use dispc_ops

Change omapdrm to get dispc_ops and use that to call the dispc functions
instead or direct function calls.

The change is very straightforward.

The only problem was in omap_crtc_init() which calls pipe2vbl(crtc), and
at that point of time the crtc->dev link, which is used to get the
dispc_ops, has not been set up yet. This patch makes omap_crtc_init()
skip the call to pipe2vbl() and instead calls
dispc_ops->mgr_get_vsync_irq() directly.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/omap_drv.h

@@ -59,6 +59,8 @@ int omap_irq_wait(struct drm_device *dev, struct omap_irq_wait *wait,
 struct omap_drm_private {
 	uint32_t omaprev;
 
+	const struct dispc_ops *dispc_ops;
+
 	unsigned int num_crtcs;
 	struct drm_crtc *crtcs[8];