scsi: ibmvfc: Define Sub-CRQ interrupt handler routine

Simple handler that calls Sub-CRQ drain routine directly.

Link: https://lore.kernel.org/r/20210114203148.246656-11-tyreld@linux.ibm.comReviewed-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NTyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ibmvscsi/ibmvfc.c

@@ -3571,6 +3571,16 @@ static void ibmvfc_drain_sub_crq(struct ibmvfc_queue *scrq)
 	}
 }
 
+static irqreturn_t ibmvfc_interrupt_scsi(int irq, void *scrq_instance)
+{
+	struct ibmvfc_queue *scrq = (struct ibmvfc_queue *)scrq_instance;
+
+	ibmvfc_toggle_scrq_irq(scrq, 0);
+	ibmvfc_drain_sub_crq(scrq);
+
+	return IRQ_HANDLED;
+}
+
 /**
  * ibmvfc_init_tgt - Set the next init job step for the target
  * @tgt:		ibmvfc target struct