rte_eth_linkstatus_set() returns 0 when link up status changes.
Fixes: 4abe903e5078 ("net/sfc: use link status helper functions") Cc: stable@dpdk.org Reported-by: Shuki Katzenelson <shuki@lightbitslabs.com> Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>