staging: fsl-dpaa2/eth: Use implicit clear of link interrupt

dpni_get_irq_status() also looks at the input value of its
status parameter, and if not null it automatically clears
from pending state the bits that are set there.

Use this feature to avoid a separate MC command for clearing
the interrupt event bits after reading the status.
Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c

@@ -2332,7 +2332,7 @@ static irqreturn_t dpni_irq0_handler(int irq_num, void *arg)
 
 static irqreturn_t dpni_irq0_handler_thread(int irq_num, void *arg)
 {
-	u32 status = 0, clear = 0;
+	u32 status = ~0;
 	struct device *dev = (struct device *)arg;
 	struct fsl_mc_device *dpni_dev = to_fsl_mc_device(dev);
 	struct net_device *net_dev = dev_get_drvdata(dev);
@@ -2342,18 +2342,12 @@ static irqreturn_t dpni_irq0_handler_thread(int irq_num, void *arg)
 				  DPNI_IRQ_INDEX, &status);
 	if (unlikely(err)) {
 		netdev_err(net_dev, "Can't get irq status (err %d)\n", err);
-		clear = 0xffffffff;
-		goto out;
+		return IRQ_HANDLED;
 	}
 
-	if (status & DPNI_IRQ_EVENT_LINK_CHANGED) {
-		clear |= DPNI_IRQ_EVENT_LINK_CHANGED;
+	if (status & DPNI_IRQ_EVENT_LINK_CHANGED)
 		link_state_update(netdev_priv(net_dev));
-	}
 
-out:
-	dpni_clear_irq_status(dpni_dev->mc_io, 0, dpni_dev->mc_handle,
-			      DPNI_IRQ_INDEX, clear);
 	return IRQ_HANDLED;
 }