qcom: ice: Expose an API to setup ICE hardware

New ICE hardware requires power regulators, clocks, bus vote to be
enabled and set properly before key registers can be read/written.
Earlier, caller was explicitly doing this job. Now, it is becoming
complex and hence moving all ICE setup related functionalities to
ICE driver. ICE driver would expose an API that callers can call.

Change-Id: I378c08bb7350bd1c2c616ce56dc52c18c2305c4a
Signed-off-by: Dinesh K Garg <dineshg@codeaurora.org>