clk: mvebu: disintegrate obsolete file

Switch from function-centric to soc-centric clock drivers now makes
a bunch of files obsolete. This deletes all files and Kconfig options
that are not required anymore.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>