idpf: cancel mailbox work in error path

In idpf_vc_core_init, the mailbox work is queued
on a mailbox workqueue but it is not cancelled on error.
This results in a call trace when idpf_mbx_task tries
to access the freed mailbox queue pointer. Fix it by
cancelling the mailbox work in the error path.

Fixes: 4930fbf ("idpf: add core init and interrupt request")
Reviewed-by: Wojciech Drewek <[email protected]>
Signed-off-by: Pavan Kumar Linga <[email protected]>
Tested-by: Krishneil Singh  <[email protected]>
Signed-off-by: Jacob Keller <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: plinga1

drivers/net/ethernet/intel/idpf/idpf_virtchnl.c

@@ -3146,6 +3146,7 @@ int idpf_vc_core_init(struct idpf_adapter *adapter)
 
 err_intr_req:
 	cancel_delayed_work_sync(&adapter->serv_task);
+	cancel_delayed_work_sync(&adapter->mbx_task);
 	idpf_vport_params_buf_rel(adapter);
 err_netdev_alloc:
 	kfree(adapter->vports);