api: pktio: add pktio index conversion API
api: pktio: add pktio index conversion API

Add the odp_pktio_index() API to enable applications to convert packet I/O
handles to indices for managing user contexts and related associated data.

Signed-off-by: Bill Fischofer <52f3c909d51cc5d355a68a403df6906b3c1a8f83@linaro.org>
Reviewed-by: Bogdan Pricope <385103c4eae27e55111df6ab7856eefb0647e14e@enea.com>
Reviewed-by: Petri Savolainen <d528fd253b9aaf78fa72edbcc6249e82047f6ce6@nokia.com>
Signed-off-by: Maxim Uvarov <db4d16e02ae2d7493db430203537da8b2e34f290@linaro.org>

nmorey/odp,erachmi/odp,ravineet-singh/odp,erachmi/odp,ravineet-singh/odp,dkrot/odp,nmorey/odp,dkrot/odp,erachmi/odp,ravineet-singh/odp,erachmi/odp,mike-holmes-linaro/odp,mike-holmes-linaro/odp,dkrot/odp,ravineet-singh/odp,nmorey/odp,nmorey/odp,mike-holmes-linaro/odp,mike-holmes-linaro/odp,dkrot/odp