[libpng14] Imported from libpng-1.4.20rc01.tar

pngtest.c

@@ -1737,4 +1737,4 @@ main(int argc, char *argv[])
 }
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef version_1_4_20beta01 your_png_h_is_not_version_1_4_20beta01;
+typedef version_1_4_20rc01 your_png_h_is_not_version_1_4_20rc01;