test/ipfrag: check fragment offsets
test/ipfrag: check fragment offsets

Add the test content of the fragment_offset(offset and MF)
to the test_ip_frag function. Add test data for a fragment
that is not the last fragment.

Signed-off-by: Huichao Cai <dd4248da1d20ebe372551fc9630a248c9f2a0bf1@163.com>
Acked-by: Konstantin Ananyev <cbd5212b59ab42a210d72992d23a3aa17cfd3eaf@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk