drm/cma-helper: Use the generic fbdev emulation

This switches the CMA helper drivers that use its fbdev emulation over
to the generic fbdev emulation. It's the first phase of using generic
fbdev. A later phase will use DRM client callbacks for the
lastclose/hotplug/remove callbacks.

There are currently 2 fbdev init/fini functions:
- drm_fb_cma_fbdev_init/drm_fb_cma_fbdev_fini
- drm_fbdev_cma_init/drm_fbdev_cma_fini

This is because the work on generic fbdev came up during a fbdev
refactoring and thus wasn't completed. No point in completing that
refactoring when drivers will soon move to drm_fb_helper_generic_probe().

tinydrm uses drm_fb_cma_fbdev_init_with_funcs().

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703160354.59955-5-noralf@tronnes.org

include/drm/drm_fb_cma_helper.h

@@ -23,9 +23,6 @@ int drm_fb_cma_fbdev_init(struct drm_device *dev, unsigned int preferred_bpp,
 			  unsigned int max_conn_count);
 void drm_fb_cma_fbdev_fini(struct drm_device *dev);
 
-struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
-	unsigned int preferred_bpp, unsigned int max_conn_count,
-	const struct drm_framebuffer_funcs *funcs);
 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 	unsigned int preferred_bpp, unsigned int max_conn_count);
 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma);