msm: npu: suspend bw monitor before power collapse

No matter fw is alive or not, bw monitor needs to be suspended before
power collapse.

CRs-Fixed: 2271897
Change-Id: If41a47b65181c2c44d680f1314ea45c9de0ea11b
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>