Fix "make vgtest" so it runs to the end (but now it fails ;)

Signed-off-by: Claire Xenia Wolf <claire@clairexen.net>

tests/simple/string_format.v

@@ -1,4 +1,4 @@
-module top;
+module string_format_top;
 	parameter STR = "something interesting";
 	initial begin
 		$display("A: %s", STR);