Fixed hook documentation for removed hooks

Removed hook definitions for UserComparePasswords
and UserCryptPassword, rather than keep them in
the file.

Bug: 28419
Change-Id: I7bfda155986d1407caef4e3890024c5b8a66fdcc
Follows-up: I0a9c972931a0eff0cfb2619cef3ddffd03710285
Merge "Fixed hook documentation for removed hooks"