pgsql: doc: Fix incorrect entries generated from wait_event_names.txt

doc: Fix incorrect entries generated from wait_event_names.txt

fa88928 has introduced wait_event_names.txt, and some of its entries had
some documentation fields with more information than necessary.

This commit brings back the description of all the wait events to be
consistent with the older stable branches.  Five descriptions were
incorrect.

Author: Bertrand Drouvot
Discussion: https://postgr.es/m/e378989e-1899-643a-dec1-10f691a0a105@gmail.com

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/f05b1fa1ff5b2133d636a427d00fe85eedad49b3

Modified Files
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src/backend/utils/activity/wait_event_names.txt | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)