i40e: Store the irq number in i40e_q_vector

Make it easy to figure out the IRQ number for a particular i40e_q_vector by
storing the assigned IRQ in the structure itself.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/i40e/i40e.h

@@ -992,6 +992,7 @@ struct i40e_q_vector {
 	struct rcu_head rcu;	/* to avoid race with update stats on free */
 	char name[I40E_INT_NAME_STR_LEN];
 	bool arm_wb_state;
+	int irq_num;		/* IRQ assigned to this q_vector */
 } ____cacheline_internodealigned_in_smp;
 
 /* lan device */

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -4123,6 +4123,7 @@ static int i40e_vsi_request_irq_msix(struct i40e_vsi *vsi, char *basename)
 		}
 
 		/* register for affinity change notifications */
+		q_vector->irq_num = irq_num;
 		q_vector->affinity_notify.notify = i40e_irq_affinity_notify;
 		q_vector->affinity_notify.release = i40e_irq_affinity_release;
 		irq_set_affinity_notifier(irq_num, &q_vector->affinity_notify);