clk: msm: clock-osm: Do not initialize ACD if the cluster isn't online

The OSM clock driver currently enables ACD for the silver and
gold clusters regardless of whether they've been brought up or
not. ACD requires the cluster PLLs to be running for initialization,
a requirement which would not be met if the cluster hasn't been
brought online.
Tie the ACD initialization sequence with enabling OSM for that
cluster.

Change-Id: Ib393dd339f8095029c9703fbe67897d0a491eced
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>