uboot-imx

x86: Add an early CMOS access library

This adds a library that provides CMOS (inside RTC SRAM) access
at a very early stage when driver model is not available yet.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>