drm/tidss: Use drmm_add_final_kfree

With this we can drop the final kfree from the release function.
Acked-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-12-daniel.vetter@ffwll.ch

drivers/gpu/drm/tidss/tidss_drv.c

@@ -17,6 +17,7 @@
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_irq.h>
+#include <drm/drm_managed.h>
 #include <drm/drm_probe_helper.h>
 
 #include "tidss_dispc.h"
@@ -109,8 +110,6 @@ static void tidss_release(struct drm_device *ddev)
 	tidss_modeset_cleanup(tidss);
 
 	drm_dev_fini(ddev);
-
-	kfree(tidss);
 }
 
 DEFINE_DRM_GEM_CMA_FOPS(tidss_fops);
@@ -154,6 +153,7 @@ static int tidss_probe(struct platform_device *pdev)
 		kfree(ddev);
 		return ret;
 	}
+	drmm_add_final_kfree(ddev, tidss);
 
 	tidss->dev = dev;
 	tidss->feat = of_device_get_match_data(dev);