pandatool: Correct header guard names (#1525)

pandatool/src/egg-optchar/config_egg_optchar.h

@@ -18,4 +18,4 @@
 
 void init_egg_optchar();
 
-#endif /* __CONFIG_UTIL_H__ */
+#endif /* CONFIG_EGG_OPTCHAR_H */

pandatool/src/palettizer/config_palettizer.h

@@ -18,4 +18,4 @@
 
 void init_palettizer();
 
-#endif /* __CONFIG_UTIL_H__ */
+#endif /* CONFIG_PALETTIZER_H */