cmake HAVE_LIB_JPEG examples

LSTS/dune cmake/Libraries/JPEG.cmake :30 

CHECK_LIBRARY_EXISTS(jpeg jpeg_set_defaults "" HAVE_LIB_JPEG)

LSTS/dune cmake/Libraries/JPEG.cmake :37 

else(HAVE_LIB_JPEG AND DUNE_SYS_HAS_JPEGLIB_H)

LSTS/dune cmake/Libraries/JPEG.cmake :40 

endif(HAVE_LIB_JPEG AND DUNE_SYS_HAS_JPEGLIB_H)