[PATCH v2] cryptodev: add missing doc

[Akhil Goyal]

> Subject: [PATCH v2] cryptodev: add missing doc
Title updated as "cryptodev: fix missing doc"
> 
> Description for rte_cryptodev_get_sec_ctx is missing. Add the same.
> 
> Fixes: eadb4fa1e1fe ("cryptodev: support security APIs")
> 
> Signed-off-by: Anoob Joseph <anoobj at marvell.com>
Acked-by: Akhil Goyal <gakhil at marvell.com>

Cc: stable at dpdk.org
Applied to dpdk-next-crypto