patch 8.1.0564: setting v:errors to wrong type still possible

Problem:    Setting v:errors to wrong type still possible.
Solution:   Return after giving an error message. (Christian Brabandt)
diff --git a/src/eval.c b/src/eval.c
index 1dae2bf..8839e05 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -7568,7 +7568,10 @@
 		return;
 	    }
 	    else if (v->di_tv.v_type != tv->v_type)
+	    {
 		EMSG2(_("E963: setting %s to value with wrong type"), name);
+		return;
+	    }
 	}
 
 	clear_tv(&v->di_tv);