ecore: don't artificially block fonctionnality for nested loop.

We do have nested loop when manually calling iterate and was used
in legacy code that got broken with this change.

src/lib/ecore/ecore_main.c

@@ -1159,11 +1159,6 @@ _ecore_main_loop_begin(Eo *obj, Efl_Loop_Data *pd)
 {
    if (obj == ML_OBJ)
      {
-        if (pd->in_loop > 0)
-          {
-             ERR("Beginning main loop() inside an existing main loop");
-             return;
-          }
 #ifdef HAVE_SYSTEMD
         sd_notify(0, "READY=1");
 #endif