dm: core: Add logging on unbind failure

This failure path is tricky to debug since it continues after failure and
there are a lot of error paths. Add logging to help.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c
index 58b19a4..b24b677 100644
--- a/drivers/core/uclass.c
+++ b/drivers/core/uclass.c
@@ -120,10 +120,10 @@
 				       uclass_node);
 		ret = device_remove(dev, DM_REMOVE_NORMAL);
 		if (ret)
-			return ret;
+			return log_msg_ret("remove", ret);
 		ret = device_unbind(dev);
 		if (ret)
-			return ret;
+			return log_msg_ret("unbind", ret);
 	}
 
 	uc_drv = uc->uc_drv;