examples/bond: fix FreeBSD build

examples/bond: fix FreeBSD build

Error:
examples/bond/main.c:431:24: error: use of undeclared identifier 'AF_INET'

AF_INET defined in sys/socket.h

This header included for Linux:
. /<snip>/include/rte_ip.h
.. /usr/include/netinet/in.h
... /usr/include/sys/socket.h

But not for FreeBSD:
. /<snip>/include/rte_ip.h
.. /usr/include/netinet/in.h
... /usr/include/machine/endian.h
... /usr/include/netinet6/in6.h
. /<snip>/include/rte_tcp.h

Signed-off-by: Daniel Mrzyglod <danielx.t.mrzyglod@intel.com>
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>