ARM: imx6q-sabrelite: Rename 'pinctrl_gpio_hog'

'pinctrl_gpio_hog' is used to setup the pin functions, and it is not
neccesarily used only for GPIO pins, so remove 'gpio' from its name
to describe a more generic term.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>