drm/radeon: fix pixcache and purge/cache flushing registers

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/char/drm/r300_reg.h b/drivers/char/drm/r300_reg.h
index 8f664af..a72c703 100644
--- a/drivers/char/drm/r300_reg.h
+++ b/drivers/char/drm/r300_reg.h
@@ -1346,7 +1346,7 @@
 /* Guess by Vladimir.
  * Set to 0A before 3D operations, set to 02 afterwards.
  */
-#define R300_RB3D_DSTCACHE_CTLSTAT          0x4E4C
+/*#define R300_RB3D_DSTCACHE_CTLSTAT          0x4E4C*/
 #       define R300_RB3D_DSTCACHE_UNKNOWN_02             0x00000002
 #       define R300_RB3D_DSTCACHE_UNKNOWN_0A             0x0000000A