Check for pcap_create

Using pcap create and pcap_activate should make it possible
to set the capture buffer size on Linux systems as well as Windows.
Help to implement it would be apreciated :-)

Ref:
http://seclists.org/tcpdump/2009/q3/151

svn path=/trunk/; revision=32687

acinclude.m4

@@ -614,6 +614,7 @@ install a newer version of the header file.])
 	  AC_CHECK_FUNCS(pcap_datalink_val_to_description)
 	  AC_CHECK_FUNCS(pcap_list_datalinks pcap_set_datalink pcap_lib_version)
 	  AC_CHECK_FUNCS(pcap_get_selectable_fd pcap_free_datalinks)
+	  AC_CHECK_FUNCS(pcap_create)
 	fi
 	LIBS="$ac_save_LIBS"
 ])