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: 4930fbf4 ("idpf: add core init and interrupt request")
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
Tested-by: Krishneil Singh  <krishneil.k.singh@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20231023202655.173369-3-jacob.e.keller@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

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);