Remove qdev irq sink handling

We have both IRQ sinks and GPIO inputs.  These are in principle exactly
the same thing, so remove the former.

Signed-off-by: Paul Brook <paul@codesourcery.com>
diff --git a/hw/realview.c b/hw/realview.c
index 535f907..62d8bf5 100644
--- a/hw/realview.c
+++ b/hw/realview.c
@@ -84,7 +84,7 @@
                                     cpu_irq[3], NULL);
     }
     for (n = 0; n < 64; n++) {
-        pic[n] = qdev_get_irq_sink(dev, n);
+        pic[n] = qdev_get_gpio_in(dev, n);
     }
 
     sysbus_create_simple("pl050_keyboard", 0x10006000, pic[20]);