cmake HAVE_RPC_RPC_H examples

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :420 

check_include_file(rpc/rpc.h HAVE_RPC_RPC_H)

CTSRD-CHERI/cheribsd contrib/tcpdump/CMakeLists.txt :424 

endif(HAVE_RPC_RPC_H)