ARM: tegra: add SoC UID calculation function

This is a small tool for calculation of SoC UID based on the same
Linux function. It can be further used for generation of device
unique data like mac address or exposing it as serial number.

Tested-by: Andreas Westman Dorcsak <hedmoo@yahoo.com> # ASUS Grouper E1565
Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # LG P895 T30
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>