ARM: shmobile: marzen-reference: Move clock and OF device initialisation into board...

ARM: shmobile: marzen-reference: Move clock and OF device initialisation into board code

Move the clock initialisation and OF device population from
SoC to board code. This is in keeping with the pattern used by Lager.
And the clock portion is part of decoupling clock initialisation
from SoC code in preparation for moving to the common clock framework.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
(cherry picked from commit f8fba0ce6628109bac9d33f65b637a87a2f3be24)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>