net/kni: fix config initialization

[ upstream commit dcd398f ]

When kni driver calls eth_kni_start to start device, some fields such as
min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
kni_ioctl_create create a kni netdevice with a random min_mtu and
max_mtu value. This is unexpected and sometimes we could not change the
kni device mtu with ip link command.

Fixes: ff1e35f ("kni: calculate MTU from mbuf size")

Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

drivers/net/kni/rte_eth_kni.c

@@ -124,7 +124,7 @@ eth_kni_start(struct rte_eth_dev *dev)
 	struct pmd_internals *internals = dev->data->dev_private;
 	uint16_t port_id = dev->data->port_id;
 	struct rte_mempool *mb_pool;
-	struct rte_kni_conf conf;
+	struct rte_kni_conf conf = {{0}};
 	const char *name = dev->device->name + 4; /* remove net_ */
 
 	mb_pool = internals->rx_queues[0].mb_pool;