imx: mxc_gpio: add support for imx7d SoC

* Add mxc_gpio support for imx7d SoC
* Use CONFIG_MX7 to extend mxc gpio driver support for imx7d

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Signed-off-by: Adrian Alonso <aalonso@freescale.com>
2 files changed