The pinctrl properties on the IOMUXC node get overwritten by the
carrier board level device tree, hence the pinctrl_reset_moci
pinctrl does not get applied.

Associate the pinctrl_reset_moci pinctrl with the PCIe node where
we also make use of the pin as a reset GPIO.

Since the pin is muxed as a GPIO by default not muxing it explicitly
worked fine in practise.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>