msm: vidc: Scale clocks with perf level change

When client calls perf level change, driver needs to
make sure that it scales clocks to make the perf level
change effect immediately.

Change-Id: I6510bf14ea28ac09513610a4e7f31446ca499ec0
Signed-off-by: Praneeth Paladugu <ppaladug@codeaurora.org>