uboot-imx

i.MX6UL: isiot: Add SETUP_IOMUX_PADS

Add generic SETUP_IOMUX_PADS function, for imx6ul mux pads
and use them in Is.IoT board.

Cc: Stefano Babic <sbabic@denx.de>
Cc: Matteo Lisi <matteo.lisi@engicam.com>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>