drm/zte: 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>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180926120650.25614-1-tzimmermann@suse.de

drivers/gpu/drm/zte/zx_drm_drv.c

@@ -114,7 +114,7 @@ static int zx_drm_bind(struct device *dev)
 	component_unbind_all(dev, drm);
 out_unregister:
 	dev_set_drvdata(dev, NULL);
-	drm_dev_unref(drm);
+	drm_dev_put(drm);
 	return ret;
 }
 
@@ -127,7 +127,7 @@ static void zx_drm_unbind(struct device *dev)
 	drm_mode_config_cleanup(drm);
 	component_unbind_all(dev, drm);
 	dev_set_drvdata(dev, NULL);
-	drm_dev_unref(drm);
+	drm_dev_put(drm);
 }
 
 static const struct component_master_ops zx_drm_master_ops = {