cmake HAVE_LIBPNG_PNG_H examples

plumonito/dtslam 3rdparty/opencv-git/cmake/OpenCVFindLibsGrfmt.cmake :159 

check_include_file("${PNG_PNG_INCLUDE_DIR}/libpng/png.h" HAVE_LIBPNG_PNG_H)

DCMTK/dcmtk CMake/GenerateDCMTKConfigure.cmake :370 

CHECK_INCLUDE_FILE_CXX("libpng/png.h" HAVE_LIBPNG_PNG_H)

joachimBurket/esp32-opencv cmake/OpenCVFindLibsGrfmt.cmake :188 

check_include_file("${PNG_PNG_INCLUDE_DIR}/libpng/png.h" HAVE_LIBPNG_PNG_H)

SsageParuders/Android_Native_Surface my_android_opencv/cmake/OpenCVFindLibsGrfmt.cmake :233 

check_include_file("${PNG_PNG_INCLUDE_DIR}/libpng/png.h" HAVE_LIBPNG_PNG_H)