drm/i915: show interrupt info on IVB

IVB uses the same interrupt reg layout as SNB, so add an IS_GEN7 to the
interrupt debugfs file.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NKeith Packard <keithp@keithp.com>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -499,7 +499,7 @@ static int i915_interrupt_info(struct seq_file *m, void *data)
 	seq_printf(m, "Interrupts received: %d\n",
 		   atomic_read(&dev_priv->irq_received));
 	for (i = 0; i < I915_NUM_RINGS; i++) {
-		if (IS_GEN6(dev)) {
+		if (IS_GEN6(dev) || IS_GEN7(dev)) {
 			seq_printf(m, "Graphics Interrupt mask (%s):	%08x\n",
 				   dev_priv->ring[i].name,
 				   I915_READ_IMR(&dev_priv->ring[i]));