[libpng15] Make pnglibconf.h a public header in CmakeLists.txt
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 319bb1b..748aea5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -269,13 +269,13 @@
 set(libpng_public_hdrs
   png.h
   pngconf.h
+  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
 )
 set(libpng_private_hdrs
   pngpriv.h
   pngdebug.h
   pnginfo.h
   pngstruct.h
-  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
 )
 set(libpng_sources
   ${libpng_public_hdrs}