Parser: Fix fetch_section_first when the section doesn't exist

src/config.c

@@ -561,6 +561,7 @@ conf_menu_section(void)
      struct conf_sec *menu, **set_menu, **item;
 
      menu = fetch_section_first(NULL, "menu");
+
      set_menu = fetch_section(menu, "set_menu");
 
      CHECK((conf.nmenu = fetch_section_count(set_menu)));

src/parse/parse.c

@@ -503,6 +503,9 @@ fetch_section_first(struct conf_sec *s, char *name)
                if (!strcmp(sec->name, name))
                     return sec;
 
+     if(!sec)
+          return NULL;
+
      TAILQ_FOREACH(sec, &s->sub, entry)
           if (!strcmp(sec->name, name))
                return sec;