net/enic: avoid extra unlock in MTU set

[ upstream commit e90884a65bf6d8ed0e1e5618af42cf5856a422f1 ]

The 'set_mtu_done' goto statement is being executed in a context
where the 'mtu_lock' has not been previously locked.

To avoid the extra unlocking operation, replace the goto statement
with a return statement.

Fixes: c3e0918 ("net/enic: support scatter Rx in MTU update")

Signed-off-by: Weiguo Li <liweiguo@xencore.cn>
Reviewed-by: Ferruh Yigit <ferruh.yigit@amd.com>

drivers/net/enic/enic_main.c

@@ -1630,7 +1630,7 @@ int enic_set_mtu(struct enic *enic, uint16_t new_mtu)
 	 * packet length.
 	 */
 	if (!eth_dev->data->dev_started)
-		goto set_mtu_done;
+		return rc;
 
 	/*
 	 * The device has started, re-do RQs on the fly. In the process, we