linux-phytec-fsl

MLK-13485-3 pinctrl: imx: modify the imx pinctrl to support imx7ulp gpio

On i.MX7ULP, the IOMUXC PAD register has IBE and OBE bit to control
the input/output buffer if a PIN wants to use as GPIO function.

Additonally, on i.MX7ULP, the MUX reg and CONFIG reg is shared in one
register and the GPIO function select in the MUX is not index zero as
on I.MX6 SOC, add support in code for i.MX7ULP GPIO function.

Signed-off-by: Bai Ping <ping.bai@nxp.com>
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>