profcollectd: add wakelock when recording ETM data.

The kernel may panic when trying to hibernate or hotplug
CPUs while collecting ETM data. So get wakelock to keep
the CPUs on.

Bug: 219934028
Test: run profcollectd and
Test: dumpsys suspend_control_internal --wakelocks
Change-Id: Ie1fea2b6d82d3e27d8b9553aa3967876ff7316ca
2 files changed