locksettings: improve logging of SP and protector changes

Improve the logging for synthetic password protectors being created and
deleted, and the synthetic password itself being created.  This includes
the case where a user's LSKF is being changed.

These are infrequent and important operations, so generally we should
error on the side of being verbose for them.

Bug: 268526331
Change-Id: I9cd91ecd3bb80b59fb367072d7f30dc90a5ee332
Merged-In: I9cd91ecd3bb80b59fb367072d7f30dc90a5ee332
(cherry picked from commit 72ba8378)