ethdev: remove release function for secondary process

ethdev: remove release function for secondary process

After previous changes, the function rte_eth_dev_release_port()
can be used for primary or secondary process as well.
The only difference with rte_eth_dev_release_port_secondary()
is the shared lock used in rte_eth_dev_release_port().

The function rte_eth_dev_release_port_secondary() was recently
added in 18.11 cycle.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>