cmake LIBWS2_32_HAS_GETHOSTBYADDR examples

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :446 

check_symbol_exists(gethostbyaddr "winsock2.h;ws2tcpip.h" LIBWS2_32_HAS_GETHOSTBYADDR)

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :450 

else(LIBWS2_32_HAS_GETHOSTBYADDR)

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :452 

endif(LIBWS2_32_HAS_GETHOSTBYADDR)