Suppressed warnings about non existing boot equipment files when mkisofs emulation is active

xorriso/iso_tree.c

@@ -2830,6 +2830,9 @@ int Xorriso_warn_if_not_exist(struct XorrisO *xorriso, char *prefix,
  if(ept != NULL)
    *(ept + 1)= 0;
  if(ret == -1) {
+   /* This is a normal situation with -as mkisofs emulation */
+   if(xorriso->current_interpreter == 1)
+     return(2);
    sprintf(xorriso->info_text + strlen(xorriso->info_text),
            " : path does not yet exist %s : ", where); 
  } else {