drm: Move drm_crtc_init from drm_crtc.h to drm_plane_helper.h

Just a bit of OCD cleanup on headers - this function isn't the core
interface any more but just a helper for drivers who haven't yet
transitioned to universal planes. Put the declaration at the right
spot and sprinkle necessary #includes over all drivers.

Maybe this helps to encourage driver maintainers to do the switch.

v2: Fix #include ordering for tegra, reported by 0-day builder.

v3: Include required headers, reported by Thierry.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c

@@ -26,6 +26,7 @@
  **************************************************************************/
 
 #include "vmwgfx_kms.h"
+#include <drm/drm_plane_helper.h>
 
 
 #define vmw_crtc_to_ldu(x) \

drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c

@@ -26,6 +26,7 @@
  **************************************************************************/
 
 #include "vmwgfx_kms.h"
+#include <drm/drm_plane_helper.h>
 
 
 #define vmw_crtc_to_sou(x) \