ethdev: extend RSS offload types

ethdev: extend RSS offload types

This patch reserves several bits as input set selection from the
high end of the 64 bits. It is combined with exisiting ETH_RSS_*
to represent RSS types. This patch also checks the simultaneous
use of SRC_ONLY and DST_ONLY of the same level.

Signed-off-by: Simei Su <simei.su@intel.com>
Reviewed-by: Qi Zhang <qi.z.zhang@intel.com>
Acked-by: Ori Kam <orika@mellanox.com>
Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>