api: pktio: adds further definition for classification configuration
api: pktio: adds further definition for classification configuration

Updates classification configuration documentation.

Signed-off-by: Balasubramanian Manoharan <affd9aba178b6c6e9aaff69252817fd03d71ae35@linaro.org>
Reviewed-by: Petri Savolainen <d528fd253b9aaf78fa72edbcc6249e82047f6ce6@nokia.com>
Signed-off-by: Maxim Uvarov <db4d16e02ae2d7493db430203537da8b2e34f290@linaro.org>

erachmi/odp,erachmi/odp,erachmi/odp,erachmi/odp