drm: simplify the return expression of ast_drm_resume()

Simplify the return expression.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220505022208.57157-1-chi.minghao@zte.com.cn

drivers/gpu/drm/ast/ast_drv.c

@@ -159,15 +159,10 @@ static int ast_drm_thaw(struct drm_device *dev)
 
 static int ast_drm_resume(struct drm_device *dev)
 {
-	int ret;
-
 	if (pci_enable_device(to_pci_dev(dev->dev)))
 		return -EIO;
 
-	ret = ast_drm_thaw(dev);
-	if (ret)
-		return ret;
-	return 0;
+	return ast_drm_thaw(dev);
 }
 
 static int ast_pm_suspend(struct device *dev)