soc: qcom: sleepstate: Increase notifier priority

Remote processors may have race conditions if the notification
that the local processor is suspending comes late. This change
increases the priority of our suspend notifier block.

CRs-Fixed: 2045408
Change-Id: Ifb398c1fcf584a5dd6d53fc47ca66d01718c74b5
Signed-off-by: Chris Lew <clew@codeaurora.org>