msm: npu: Set npu bandwidth during power on/off

Minimum bandwidth needs to be requested before turning on npu
clocks. And it needs to be cleared when turning off npu clocks.
This change is to move the bandwidth setting to power on/off
functions.

Change-Id: Ifa98587cde6423955c0a907169e24da8a17a774e
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>