i965g: avoid void * arithmetic
diff --git a/src/gallium/winsys/i965/drm/i965_drm_buffer.c b/src/gallium/winsys/i965/drm/i965_drm_buffer.c
index 33a1749..fb5e50c 100644
--- a/src/gallium/winsys/i965/drm/i965_drm_buffer.c
+++ b/src/gallium/winsys/i965/drm/i965_drm_buffer.c
@@ -463,7 +463,7 @@
       brw_dump_data( idws->id,
 		     buf->data_type,
 		     buf->bo->offset + offset, 
-		     buf->bo->virtual + offset, 
+		     (char*)buf->bo->virtual + offset, 
 		     length );
 }