drm/udl: Use fbdev-shmem

Implement fbdev emulation with fbdev-shmem. Avoids the overhead of
fbdev-generic's additional shadow buffering. No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-19-tzimmermann@suse.de

drivers/gpu/drm/udl/udl_drv.c

@@ -6,7 +6,7 @@
 #include <linux/module.h>
 
 #include <drm/drm_drv.h>
-#include <drm/drm_fbdev_generic.h>
+#include <drm/drm_fbdev_shmem.h>
 #include <drm/drm_file.h>
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_managed.h>
@@ -117,7 +117,7 @@ static int udl_usb_probe(struct usb_interface *interface,
 
 	DRM_INFO("Initialized udl on minor %d\n", udl->drm.primary->index);
 
-	drm_fbdev_generic_setup(&udl->drm, 0);
+	drm_fbdev_shmem_setup(&udl->drm, 0);
 
 	return 0;
 }