From: Harry Wei <harryxiyou@gmail.com>
When i compile kernel, it shows me two warnings
like below, so this patch can fix them. 

[...]
CC [M]  drivers/gpu/drm/i915/intel_dvo.o
CC [M]  drivers/gpu/drm/i915/intel_ringbuffer.o
drivers/gpu/drm/i915/intel_ringbuffer.c:603: warning: ���ring_get_irq��� defined but not used
drivers/gpu/drm/i915/intel_ringbuffer.c:620: warning: ���ring_put_irq��� defined but not used
CC [M]  drivers/gpu/drm/i915/intel_overlay.o
CC [M]  drivers/gpu/drm/i915/intel_opregion.o
[...]


Signed-off-by: Harry Wei <harryxiyou@gmail.com>

Index: prj/drivers/gpu/drm/i915/intel_ringbuffer.c
===================================================================
--- prj.orig/drivers/gpu/drm/i915/intel_ringbuffer.c	2011-06-03 20:37:35.523539547 +0800
+++ prj/drivers/gpu/drm/i915/intel_ringbuffer.c	2011-06-03 20:38:07.279539574 +0800
@@ -599,23 +599,6 @@
 	return 0;
 }
 
-static bool
-ring_get_irq(struct intel_ring_buffer *ring, u32 flag)
-{
-	struct drm_device *dev = ring->dev;
-	drm_i915_private_t *dev_priv = dev->dev_private;
-
-	if (!dev->irq_enabled)
-	       return false;
-
-	spin_lock(&ring->irq_lock);
-	if (ring->irq_refcount++ == 0)
-		ironlake_enable_irq(dev_priv, flag);
-	spin_unlock(&ring->irq_lock);
-
-	return true;
-}
-
 static void
 ring_put_irq(struct intel_ring_buffer *ring, u32 flag)
 {