examples/ipsec-secgw: fix first packet with inline crypto

examples/ipsec-secgw: fix first packet with inline crypto

Inline crypto installs a flow rule in the NIC. This flow
rule must be installed before the first inbound packet is
received.

The create_session() function installs the flow rule,
create_session() has been refactored into create_inline_session()
and create_lookaside_session(). The create_inline_session() function
uses the socket_ctx data and is now called at initialisation in
sa_add_rules().

The max_session_size() function has been added to calculate memory
requirements.

The cryprodev_init() function has been refactored to drop calls to
rte_mempool_create() and to drop calculation of memory requirements.

The main() function has been refactored to call max_session_size() and
to call session_pool_init() and session_priv_pool_init() earlier.
The ports are started now before adding a flow rule in main().
The sa_init(), sp4_init(), sp6_init() and rt_init() functions are
now called after the ports have been started.

The rte_ipsec_session_prepare() function is called in fill_ipsec_session()
for inline which is called from the ipsec_sa_init() function.

Fixes: ec17993a145a ("examples/ipsec-secgw: support security offload")
Fixes: d299106e8e31 ("examples/ipsec-secgw: add IPsec sample application")
Cc: stable@dpdk.org
Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>