hash: allow to store data in hash table

hash: allow to store data in hash table

Usually hash tables not only store keys, but also data associated
to them. In order to maintain the existing API, the old functions
will still return the index where the key was stored.
The new functions will return the data associated to that key.
In the case of the lookup_bulk function, it will return also
the number of entries found and a bitmask of which entries
were found.

Unit tests have been updated to use these new functions.

As a final point, a flag has been added in rte_hash_parameters
to indicate if there are new parameters for future versions,
so there is no need to maintain multiple versions
of the existing functions in the future.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
[Thomas: fix || operator in a precondition check]