Change tests/hoobr_bfd_print.pcap to test the BFD printer again.

Clamp the on-the-wire length values of the packets at 262144, so that we
hand the packets to the BFD printer, rather than just bailing out before
we ever get there.

Author: guyharris

tests/hoobr_bfd_print.out

@@ -1,3 +1,7 @@
-    1  [Invalid header: len(808464432) > 262144]
-    2  [Invalid header: len(808464432) > 262144]
+    1  05:27:12.808464432 30:30:30:30:30:30 > 30:30:30:30:30:30, ethertype Unknown (0x3030), length 262144: 
+	0x0000:  3030 3030 3030 3030 3030 3030 3030 3030  0000000000000000
+	0x0010:  3030 3030 3030 3030 3030 3030            000000000000
+    2  05:27:12.808464432 30:30:30:30:30:30 > 30:30:30:30:30:30, ethertype Unknown (0x3030), length 262144: 
+	0x0000:  3030 3030 3030 3030 3030 3030 3030 3030  0000000000000000
+	0x0010:  3030 3030 3030 3030 3030 3030            000000000000
     3  05:27:12.808464432 IP truncated-ip - 14 bytes missing! 48.48.48.48.12336 > 48.48.48.48.3785: BFD, Echo, length: 12308