ARM: oxnas: Add OX820 config and makefile entry

Refactor the oxnas Kconfig entries among the OX810SE and OX820 configs,
and add the files to support the OX820 SMP feature.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
2 files changed