This converts the following to Kconfig:
CONFIG_MXS_GPIO
Travis-CI: https://travis-ci.org/lmajewski/u-boot-dfu/builds/571260789
Signed-off-by: Lukasz Majewski <lukma@denx.de>
Acked-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>