cmake HAVE_LIBNSL examples

FujiNetWIFI/fujinet-firmware components_pc/libssh/ConfigureChecks.cmake :244 

check_library_exists(nsl inet_pton "" HAVE_LIBNSL)

FujiNetWIFI/fujinet-firmware components_pc/libssh/ConfigureChecks.cmake :247 

endif (HAVE_LIBNSL)

v6d-io/v6d cmake/FindLibUV.cmake :56 

check_library_exists(nsl gethostbyname "nsl.h" HAVE_LIBNSL)