dmaengine: ioatdma: fix coccinelle warning

Simplifying the end return. This existed in the original code but was
flagged when refactoring of the code made it appear it's new.

coccinelle warnings: (new ones prefixed by >>)

>> drivers/dma/ioat/init.c:1018:1-3: WARNING: end returns can be simpified
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

drivers/dma/ioat/init.c

@@ -1008,16 +1008,15 @@ static int ioat_xor_val_self_test(struct ioatdma_device *ioat_dma)
 
 static int ioat3_dma_self_test(struct ioatdma_device *ioat_dma)
 {
-	int rc = ioat_dma_self_test(ioat_dma);
+	int rc;
 
+	rc = ioat_dma_self_test(ioat_dma);
 	if (rc)
 		return rc;
 
 	rc = ioat_xor_val_self_test(ioat_dma);
-	if (rc)
-		return rc;
 
-	return 0;
+	return rc;
 }
 
 static void ioat_intr_quirk(struct ioatdma_device *ioat_dma)