drm/i915: Emit telltales for extra levels of debug upon initialisation

After printing our welcome message to the user, also include
supplementary details on what debugging is enabled (useful for us to
sanity check what extra safeguards are on for any random kernel).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20161014132707.29039-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 1fddc2c..912d534 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1232,6 +1232,10 @@
 	DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
 		 driver.name, driver.major, driver.minor, driver.patchlevel,
 		 driver.date, pci_name(pdev), dev_priv->drm.primary->index);
+	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG))
+		DRM_INFO("DRM_I915_DEBUG enabled\n");
+	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
+		DRM_INFO("DRM_I915_DEBUG_GEM enabled\n");
 
 	intel_runtime_pm_put(dev_priv);