drm: update PCIGART support from CVS

In order to work on FreeBSD the gart needed to use a local mapping
This patch moves the mainline to the new code and aligns some comment
changes

From: Eric Anholt <anholt@freebsd.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/r128_drv.h b/drivers/char/drm/r128_drv.h
index 9a779ba..94abffb 100644
--- a/drivers/char/drm/r128_drv.h
+++ b/drivers/char/drm/r128_drv.h
@@ -1,7 +1,7 @@
 /* r128_drv.h -- Private header for r128 driver -*- linux-c -*-
  * Created: Mon Dec 13 09:51:11 1999 by faith@precisioninsight.com
- *
- * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ */
+/* Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  * All rights reserved.
  *