drivers: soc: Allow building the amlogic drivers without ARCH_MESON

The current condition makes it difficult to compile the amlogic/
drivers with COMPILE_TEST, or without ARCH_MESON in general.

Fixes kbuild errors with patch series that depend on drivers in that
directory, for instance the meson video decoder.

Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>