Thread: pgsql: Remove unused wait events.

Remove unused wait events.

Commit 464824323e introduced the wait events which were neither used by
that commit nor by follow-up commits for that work.

Author: Masahiro Ikeda
Backpatch-through: 14, where it was introduced
Discussion: https://postgr.es/m/ff077840-3ab2-04dd-bbe4-4f5dfd2ad481@oss.nttdata.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/1607cd0b6c9919bf765198882ea48a98e901e1bc

Modified Files
--------------
doc/src/sgml/monitoring.sgml            | 16 ----------------
src/backend/utils/activity/wait_event.c | 12 ------------
src/include/utils/wait_event.h          |  6 +-----
3 files changed, 1 insertion(+), 33 deletions(-)