Fixing bug in bootanalyze when the event time is 0 am: 9f0e7264b2 am: b767a7b2cd

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/extras/+/11829463

Change-Id: Ie1e5d60dd4f0028ac316e9e07f637cd90c2e54e9