ethdev: remove jumbo offload flag

ethdev: remove jumbo offload flag

Removing 'DEV_RX_OFFLOAD_JUMBO_FRAME' offload flag.

Instead of drivers announce this capability, application can deduct the
capability by checking reported 'dev_info.max_mtu' or
'dev_info.max_rx_pktlen'.

And instead of application setting this flag explicitly to enable jumbo
frames, this can be deduced by driver by comparing requested 'mtu' to
'RTE_ETHER_MTU'.

Removing this additional configuration for simplification.

Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Rosen Xu <rosen.xu@intel.com>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Acked-by: Hyong Youb Kim <hyonkim@cisco.com>
Acked-by: Michal Krawczyk <mk@semihalf.com>