pgsql: Fix typos and some format mistakes in comments

Fix typos and some format mistakes in comments

Author: Justin Pryzby
Discussion: /messages/by-id/20200612023709.GC14879@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/aaf8c990502f7bb28c10f6bab1d23fe2f9f0b537

Modified Files
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src/backend/replication/logical/origin.c | 2 +-
src/backend/replication/logical/relation.c | 2 +-
src/backend/utils/mmgr/README | 2 +-
src/bin/pg_dump/pg_backup_archiver.c | 6 +++---
src/bin/pg_dump/pg_backup_custom.c | 8 +++-----
5 files changed, 9 insertions(+), 11 deletions(-)