nvme-pci: cleanup nvme_irq()

Get rid of a local variable that is not needed and just return the
status directly.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/pci.c

@@ -1060,12 +1060,10 @@ static inline int nvme_process_cq(struct nvme_queue *nvmeq)
 static irqreturn_t nvme_irq(int irq, void *data)
 {
 	struct nvme_queue *nvmeq = data;
-	irqreturn_t ret = IRQ_NONE;
 
 	if (nvme_process_cq(nvmeq))
-		ret = IRQ_HANDLED;
-
-	return ret;
+		return IRQ_HANDLED;
+	return IRQ_NONE;
 }
 
 static irqreturn_t nvme_irq_check(int irq, void *data)