drivers/net: advertise no support for keeping flow rules

drivers/net: advertise no support for keeping flow rules

When RTE_ETH_DEV_CAPA_FLOW_RULE_KEEP capability bit is zero,
the specified behavior is the same as it had been before
this bit was introduced. Explicitly reset it in all PMDs
supporting rte_flow API in order to attract the attention
of maintainers, who should eventually choose to advertise
the new capability or not. It is already known that
mlx4 and mlx5 will not support this capability.

For RTE_ETH_DEV_CAPA_FLOW_SHARED_OBJECT_KEEP
similar action is not performed,
because no PMD except mlx5 supports indirect actions.
Any PMD that starts doing so will anyway have to consider
all relevant API, including this capability.

Suggested-by: Ferruh Yigit <ferruh.yigit@intel.com>
Signed-off-by: Dmitry Kozlyuk <dkozlyuk@nvidia.com>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>
Acked-by: Hyong Youb Kim <hyonkim@cisco.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>