cmake HAVE_PCAP_FREECODE examples

usb-tools/USBProxy-legacy src/cmake/modules/FindPCAP.cmake :106 

CHECK_FUNCTION_EXISTS("pcap_freecode" HAVE_PCAP_FREECODE)

boundary/wireshark cmake/modules/FindPCAP.cmake :115 

CHECK_FUNCTION_EXISTS("pcap_freecode" HAVE_PCAP_FREECODE)

gnss-sdr/gnss-sdr cmake/Modules/FindPCAP.cmake :121 

check_function_exists("pcap_freecode" HAVE_PCAP_FREECODE)