ARM: dts: uniphier: factor out common nodes to uniphier-common32.dtsi

UniPhier SoCs (except PH1-sLD3) have several nodes in common.
Factor out them into uniphier-common32.dtsi.  This improves the code
maintainability.

PH1-sLD3 is so old that it has more or less different register maps
than the others.  So, it cannot be included in this refactoring.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>