msm: ipa3: fix a race condition on clock vote from suspend

There is a potential race condition where suspend interrupt
handling might be running from two different context in parallel.
Add a mutex to ensure mutual exclusion when voting for IPA clocks.

CRs-Fixed: 2037199
Change-Id: I7f14866696b6c9f5e239f3de2c4bad6991097ecb
Acked-by: Ady Abraham <adya@qti.qualcomm.com>
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>