drm/via: track user->memblock mapping with idr

Massive indirection through a hashtable for a simple key->pointer
look-up actually just adds bloat.

v2: Drop the misleading comment noted by Chris Wilson.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/via/via_map.c b/drivers/gpu/drm/via/via_map.c
index 6cca9a7..b09f659 100644
--- a/drivers/gpu/drm/via/via_map.c
+++ b/drivers/gpu/drm/via/via_map.c
@@ -104,6 +104,7 @@
 
 	dev_priv->chipset = chipset;
 
+	idr_init(&dev->object_name_idr);
 	ret = drm_sman_init(&dev_priv->sman, 2, 12, 8);
 	if (ret) {
 		kfree(dev_priv);