cmake HAVE_PCAP_STATUSTOSTR examples

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :837 

check_function_exists(pcap_statustostr HAVE_PCAP_STATUSTOSTR)

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :844 

endif(HAVE_PCAP_STATUSTOSTR)