cmake HAVE_DLSYM examples

AVSystem/Anjay CMakeLists.txt :34 

unset(HAVE_DLSYM CACHE)

AVSystem/Anjay CMakeLists.txt :35 

check_function_exists(dlsym HAVE_DLSYM)

contour-terminal/contour src/crispy/CMakeLists.txt :90 

check_function_exists(dlsym HAVE_DLSYM)