ARM: uniphier: add functions to get SoC model/revision
We sometimes have to implement different code depending on the SoC
revision. This commit adds functions to get the model/revision
number.
Note:
Model number: incremented on major changes of the SoC
Revision number: incremented on minor changes of the SoC
The "Model 2" exists for PH1-sLD3, ProXstream2/PH1-LD6b.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>