imx6q: fix I/O mapping address/size of mxs_viim.c

BugLink: http://bugs.launchpad.net/bugs/916469

The memory mapping in mxs_viim.c is incorrect with the mapping size,
and mxs_viim.c is using GPT as the first iim mapping.

Signed-off-by: Eric Miao <eric.miao@linaro.org>
2 files changed