Some invalid callback functions are provided to rte_pktmbuf_pool_init()
without their associated data causing a segmentation fault when the
function tries to use it. In this example, those callbacks are not
necessary, they can be safely replaced by NULL pointers.
Fixes: 95e8005a56e8 ("examples/l2fwd_fork: new app") Cc: stable@dpdk.org Signed-off-by: Xueming Li <xuemingl@mellanox.com>