b43: Remove unnecessary synchronize_irq() before free_irq()

Calling synchronize_irq() right before free_irq() is quite useless. On one
hand the IRQ can easily fire again before free_irq() is entered, on the
other hand free_irq() itself calls synchronize_irq() internally (in a race
condition free way), before any state associated with the IRQ is freed.

Patch was generated using the following semantic patch:
// <smpl>
@@
expression irq;
@@
-synchronize_irq(irq);
 free_irq(irq, ...);
// </smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/broadcom/b43/main.c

@@ -4375,12 +4375,10 @@ static struct b43_wldev * b43_wireless_core_stop(struct b43_wldev *dev)
 	/* Synchronize and free the interrupt handlers. Unlock to avoid deadlocks. */
 	orig_dev = dev;
 	mutex_unlock(&wl->mutex);
-	if (b43_bus_host_is_sdio(dev->dev)) {
+	if (b43_bus_host_is_sdio(dev->dev))
 		b43_sdio_free_irq(dev);
-	} else {
-		synchronize_irq(dev->dev->irq);
+	else
 		free_irq(dev->dev->irq, dev);
-	}
 	mutex_lock(&wl->mutex);
 	dev = wl->current_dev;
 	if (!dev)