cmake HAVE_IPV6_V6ONLY examples

arkdb/inception cmake/os/Windows.cmake :133 

CHECK_SYMBOL_EXISTS(IPV6_V6ONLY  "winsock2.h;ws2ipdef.h" HAVE_IPV6_V6ONLY)

google/mysql-protobuf cmake/os/Windows.cmake :146 

CHECK_SYMBOL_EXISTS(IPV6_V6ONLY  "winsock2.h;ws2ipdef.h" HAVE_IPV6_V6ONLY)

alibaba/AliSQL cmake/os/Windows.cmake :144 

CHECK_SYMBOL_EXISTS(IPV6_V6ONLY  "winsock2.h;ws2ipdef.h" HAVE_IPV6_V6ONLY)

Tokutek/mysql-5.5 cmake/os/Windows.cmake :141 

CHECK_SYMBOL_EXISTS(IPV6_V6ONLY  "winsock2.h;ws2ipdef.h" HAVE_IPV6_V6ONLY)