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

drivers/gpu/drm/i915/i915_drv.c

@@ -1232,6 +1232,10 @@ int i915_driver_load(struct pci_dev *pdev, const struct pci_device_id *ent)
 	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);