The IPU register space is 128MB, not 2GB.

Fixes: abed9a6b 'ARM i.MX53: Add IPU support'
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>