drm/tegra: Replace drm_dev_unref with drm_dev_put

This patch unifies the naming of DRM functions for reference counting
of struct drm_device. The resulting code is more aligned with the rest
of the Linux kernel interfaces.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180926115640.24755-1-tzimmermann@suse.de

drivers/gpu/drm/tegra/drm.c

@@ -1189,16 +1189,16 @@ static int host1x_drm_probe(struct host1x_device *dev)
 
 	err = drm_fb_helper_remove_conflicting_framebuffers(NULL, "tegradrmfb", false);
 	if (err < 0)
-		goto unref;
+		goto put;
 
 	err = drm_dev_register(drm, 0);
 	if (err < 0)
-		goto unref;
+		goto put;
 
 	return 0;
 
-unref:
-	drm_dev_unref(drm);
+put:
+	drm_dev_put(drm);
 	return err;
 }
 
@@ -1207,7 +1207,7 @@ static int host1x_drm_remove(struct host1x_device *dev)
 	struct drm_device *drm = dev_get_drvdata(&dev->dev);
 
 	drm_dev_unregister(drm);
-	drm_dev_unref(drm);
+	drm_dev_put(drm);
 
 	return 0;
 }