Make pcap_inject non-static, so that its prototype doesn't conflict with

the real pcap_inject in the case where we do have it.

src/util/hijack.c

  * have it.  Will almost certainly only work under Linux.
  *
  */
-static int pcap_inject ( pcap_t *pcap, const void *data, size_t len ) {
+int pcap_inject ( pcap_t *pcap, const void *data, size_t len ) {
 	int fd;
 	char *errbuf = pcap_geterr ( pcap );