i915: fix AR register restore.

Make sure the restoration correctly restores the AR registers by
flipping the ARX register into index mode before doing anything.

Without this, some people have had the text mode restore all green.
Signed-off-by: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/drm/i915_drv.c

@@ -222,6 +222,7 @@ static void i915_restore_vga(struct drm_device *dev)
 			   dev_priv->saveGR[0x18]);
 
 	/* Attribute controller registers */
+	inb(st01);
 	for (i = 0; i < 20; i++)
 		i915_write_ar(st01, i, dev_priv->saveAR[i], 0);
 	inb(st01); /* switch back to index mode */