ethdev: reset all when releasing a port

ethdev: reset all when releasing a port

The function rte_eth_dev_release_port() is partially resetting
the struct rte_eth_dev. The drivers were completing this reset
with more pointers set to NULL in the close or remove operations.

More pointers are reset at ethdev level,
and some redundant assignments are removed from PMDs.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Haiyue Wang <haiyue.wang@intel.com>
Acked-by: Jeff Guo <jia.guo@intel.com>
Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>