gpio/mxs: Change gpio-mxs into an upstanding gpio driver

    The patch makes necessary changes on gpio-mxs as below to turn it
    into an upstanding gpio driver.

     * Clean up the gpio port definition stuff

     * Use readl/writel to replace mach-specific accessors
       __raw_readl/__raw_writel

     * Change mxs_gpio_init into mxs_gpio_probe function

    And it then migrates mach-mxs to the updated driver by adding
    corresponding platform devices.

    Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
    Acked-by: Arnd Bergmann <arnd@arndb.de>
    Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
    Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
gpio/mxc: Move Freescale MXC gpio driver to drivers/gpio

    GPIO drivers are getting moved to drivers/gpio for cleanup and
    consolidation.  This patch moves the plat-mxc driver.  Follow up
    patches will clean it up and make it a fine upstanding gpio driver.

    Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
    Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
    Signed-off-by: Grant Likely <grant.likely@secretlab.ca>