scsi: ufs: let aggressive clock gating context known

It is quite possible that we might need multiple clocks to be enabled when
UFS transfers are active and we generally turn these clocks off during
runtime & system suspend. In addition, we also vote these clocks off if
aggressive clock gating feature is enabled. Idle timeout for aggressive
clock gating feature is generally ~50 milliseconds. But turning these
clocks on/off could have huge latencies hence we might only want to turn
off few essential (and low latency) clocks during aggressive clock gating.
This change adds support to let the vendor specific setup_clocks callback
know whether it is called from aggressive clock gating context or normal
clock gating context. Having this context information should help vendor
specific setup_clocks callback to selectively disable clocks.

Change-Id: I5e1523a57bc45a91faef463baac1cea2a2c8d2d6
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>