drm/renesas/rz-du: Use fbdev-dma

Implement fbdev emulation with fbdev-dma. Fbdev-dma now supports
damage handling, which is required by rz-du. Avoids the overhead of
fbdev-generic's additional shadow buffering. No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Biju Das <biju.das.jz@bp.renesas.com>
Tested-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-30-tzimmermann@suse.de

drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c

@@ -14,7 +14,7 @@
 
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_drv.h>
-#include <drm/drm_fbdev_generic.h>
+#include <drm/drm_fbdev_dma.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_probe_helper.h>
 
@@ -149,7 +149,7 @@ static int rzg2l_du_probe(struct platform_device *pdev)
 
 	drm_info(&rcdu->ddev, "Device %s probed\n", dev_name(&pdev->dev));
 
-	drm_fbdev_generic_setup(&rcdu->ddev, 32);
+	drm_fbdev_dma_setup(&rcdu->ddev, 32);
 
 	return 0;