Revert "Fixed readUserListLP() so it recovers when user 0 data is corrupted."

This reverts commit bede7f6a.

Reason for revert: the current fix fallbacks to single user, which would remove all secondary users (which in turn are the "real" users on automotive). A better approach would be just re-creating user 0 and leaving others alone (perhaps even configuring this behavior using a config boolean); I'll try that later...

Bug: 159350797
Change-Id: I259725936ce35fc94e0a1eb3f26f7efcd4b31b33
Test: N/A