PhpDoc: Set @deprecated on deprecated method
Summary: Allow IDEs to identify use of deprecated messages by using standard markup.
Test Plan: None.
Reviewers: O1 Blessed Committers, mainframe98
Reviewed By: O1 Blessed Committers, mainframe98
Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Differential Revision: https://we.phorge.it/D26484