drm/i915/guc: Rename client->cookie to match use

The client->cookie is a shadow of the doorbell->cookie value, so rename
it to indicate its association with the doorbell, like the doorbell id
and offset.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161129121024.22650-3-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 144d806..d179eae 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2414,7 +2414,7 @@ static void i915_guc_client_info(struct seq_file *m,
 	seq_printf(m, "\tPriority %d, GuC ctx index: %u, PD offset 0x%x\n",
 		client->priority, client->ctx_index, client->proc_desc_offset);
 	seq_printf(m, "\tDoorbell id %d, offset: 0x%x, cookie 0x%x\n",
-		client->doorbell_id, client->doorbell_offset, client->cookie);
+		client->doorbell_id, client->doorbell_offset, client->doorbell_cookie);
 	seq_printf(m, "\tWQ size %d, offset: 0x%x, tail %d\n",
 		client->wq_size, client->wq_offset, client->wq_tail);