net: thunderx: Fix missing destroy_workqueue of nicvf_rx_mode_wq

The nicvf_probe() won't destroy workqueue when register_netdev()
failed. Add destroy_workqueue err handle case to fix this issue.

Fixes: 2ecbe4f4

 ("net: thunderx: replace global nicvf_rx_mode_wq work queue for all VFs to private for each of them.")
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://lore.kernel.org/r/20221203094125.602812-1-liuyongqiang13@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>