ARM: dove: switch to DT clock providers

With true DT clock providers available switch Dove clock setup in DT-
enabled boards. While AUXDATA can be removed completely from bus probing,
some devices still don't know about DT at all. Therefore, some clock
aliases are created until the devices also move to DT.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>