ARM: dove: add device tree based machine descriptor

This adds a generic DT_MACHINE for mach-dove. As with other orion based
SoCs there still is some glue code required to make all internal devices
work, i.e. auxdata is provided to pass clocks to corresponding device
drivers.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>