drm/mxsfb: Use GEM DMA fbdev emulation

Use the fbdev emulation that is optimized for DMA helpers. Avoids
possible shadow buffering and makes the code simpler.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230313155138.20584-14-tzimmermann@suse.de

drivers/gpu/drm/mxsfb/mxsfb_drv.c

@@ -20,7 +20,7 @@
 #include <drm/drm_bridge.h>
 #include <drm/drm_connector.h>
 #include <drm/drm_drv.h>
-#include <drm/drm_fbdev_generic.h>
+#include <drm/drm_fbdev_dma.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
@@ -365,7 +365,7 @@ static int mxsfb_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_unload;
 
-	drm_fbdev_generic_setup(drm, 32);
+	drm_fbdev_dma_setup(drm, 32);
 
 	return 0;