drm/i915: Reinstate error level message for non-simulated gpu hangs

This seems to have been accidentally lost in

commit be62acb4cc
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Fri Aug 30 16:19:28 2013 +0300

    drm/i915: ban badly behaving contexts

Without this real gpu hangs only log output at info level, which gets
filtered away by piglit's testrunner.

v2: Tune down to notice level. Note that we need to add drm/i915 so
that at least the automatic igt dmesg filtering still picks it up.

v3: git add and lack of coffee don't mix well.

v4: Message is in between hw and sw reset, so switch verb to
continuous form.

v5: Use i915_stop_rings_allow_warn for consistency. For Chris' case of
injecting lots of hangs I guess we need to revamp this all anyway when
merging. For now this should plug the regression for piglit testing
mesa.

v6: Make it compile (Mika).

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Reported-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

drivers/gpu/drm/i915/i915_drv.c

@@ -844,6 +844,9 @@ int i915_reset(struct drm_device *dev)
 		}
 	}
 
+	if (i915_stop_ring_allow_warn(dev_priv))
+		pr_notice("drm/i915: Resetting chip after gpu hang\n");
+
 	if (ret) {
 		DRM_ERROR("Failed to reset chip: %i\n", ret);
 		mutex_unlock(&dev->struct_mutex);