SuperBuild: disable versioned output lib and then a symlink

SuperBuild/CMake/External_png.cmake

@@ -22,7 +22,7 @@ ExternalProject_Add(PNG
   -DPNG_STATIC:BOOL=OFF
   -DPNG_SHARED:BOOL=ON
   -DPNG_TESTS:BOOL=OFF
-  -DVERSIONED_OUTPUT_LIB:BOOL=ON
+  -DVERSIONED_OUTPUT_LIB:BOOL=OFF
   -DSKIP_INSTALL_FILES:BOOL=ON
   -DSKIP_INSTALL_EXECUTABLES:BOOL=OFF
   ${PNG_SB_CONFIG}