ARM: Dove: Add the audio devices in DT

This patch adds the nodes to instantiate the audio devices of the Dove
boards.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>