revert r16758, it actually produces conflicts

include/starpu.h

@@ -131,9 +131,6 @@ struct starpu_conf
 
 int starpu_conf_init(struct starpu_conf *conf);
 
-/* Defined in simgrid applications, here just making sure it will use C symbol naming convention */
-int starpu_main();
-
 int starpu_init(struct starpu_conf *conf) STARPU_WARN_UNUSED_RESULT;
 
 int starpu_initialize(struct starpu_conf *user_conf, int *argc, char ***argv);