i915g: use y-tiling when the blitter is not used

The blitter is broken. Who'd have guessed?

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

src/gallium/drivers/i915/i915_resource_texture.c

@@ -184,7 +184,10 @@ i915_texture_tiling(struct i915_screen *is, struct i915_texture *tex)
       /* XXX X-tiling might make sense */
       return I915_TILE_NONE;
 
-   return I915_TILE_X;
+   if (is->debug.use_blitter)
+      return I915_TILE_X;
+   else
+      return I915_TILE_Y;
 }