tegra-alt: adsp: add control to set min ADSP clock

tegra-alt: adsp: add control to set min ADSP clock

Certain cases like speaker protection which involve
real-time input require sudden increase in ADSP load.
ADSP DFS fails to cater such sudden increase in load
without compromising power.

Per APM control is added to set min ADSP clock when
APM is running. Min clock is restored when APM stops.

Bug 200126105
Bug 200126363

Change-Id: Icff8cee0b464f9621db0f8ba506d2e3ba307c683
Signed-off-by: Viraj Karandikar <vkarandikar@nvidia.com>
(cherry picked from commit cb5c4c718ea2e8a26126cf70da2c44e26673d531)
Reviewed-on: http://git-master/r/779169
Reviewed-by: Sumit Bhattacharya <sumitb@nvidia.com>