uboot-imx

sysreset: add syscon-reboot driver

Add a new sysreset driver based on linux/drivers/power/reset/syscon-reboot.c,
which provides a generic driver for platforms that only require writing a mask
to a regmap offset.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>