drm/i915: fix up ilk rc6 disabling confusion

While creating the new enable/disable_gt_powersave functions in

commit 8090c6b9daa04dda649ac0a2209601042abfb0a4
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sun Jun 24 16:42:32 2012 +0200

    drm/i915: wrap up gt powersave enabling functions

I've botched up the handling of ironlake_disable_rc6. Fix this up by
calling it at the right place. Note though that ironlake_disable_rc6
does a bit more than just disabling rc6 - it also tears down all the
allocated context objects.

Hence we need to move intel_teardown_rc6 out and directly call it from
intel_modeset_cleanup.

Also properly mark ironlake_enable_rc6 as static and kill the un-used
declaration in i915_drv.h.

Note: In review a question popped out why disable_rc6 also tears down
the backing object and why we should move that out - it's simply for
consistency with gen6+ rps code, which does it that way.

Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 3f58d7a..0ed02c1 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2563,7 +2563,7 @@
 	}
 }
 
-static void ironlake_teardown_rc6(struct drm_device *dev)
+void ironlake_teardown_rc6(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -2580,7 +2580,7 @@
 	}
 }
 
-void ironlake_disable_rc6(struct drm_device *dev)
+static void ironlake_disable_rc6(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -2596,8 +2596,6 @@
 		I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
 		POSTING_READ(RSTDBYCTL);
 	}
-
-	ironlake_teardown_rc6(dev);
 }
 
 static int ironlake_setup_rc6(struct drm_device *dev)
@@ -2619,7 +2617,7 @@
 	return 0;
 }
 
-void ironlake_enable_rc6(struct drm_device *dev)
+static void ironlake_enable_rc6(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_ring_buffer *ring = &dev_priv->ring[RCS];
@@ -3241,10 +3239,12 @@
 
 void intel_disable_gt_powersave(struct drm_device *dev)
 {
-	if (IS_IRONLAKE_M(dev))
+	if (IS_IRONLAKE_M(dev)) {
 		ironlake_disable_drps(dev);
-	else if (INTEL_INFO(dev)->gen >= 6 && !IS_VALLEYVIEW(dev))
+		ironlake_disable_rc6(dev);
+	} else if (INTEL_INFO(dev)->gen >= 6 && !IS_VALLEYVIEW(dev)) {
 		gen6_disable_rps(dev);
+	}
 }
 
 void intel_enable_gt_powersave(struct drm_device *dev)