uboot-imx

gpio: xilinx: Add support for using label property

Add support for reading label property from DT and set up bank name
based on that. If label property is not present full device node name is
used.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>