Fix more typos in comments.

src/backend/access/brin/brin_pageops.c

src/backend/access/heap/README.tuplock

src/backend/access/transam/twophase.c

src/backend/access/transam/xact.c

src/backend/commands/event_trigger.c

src/backend/commands/vacuumlazy.c

src/backend/postmaster/bgwriter.c

src/backend/replication/basebackup.c

src/backend/replication/logical/origin.c

src/backend/replication/logical/reorderbuffer.c

src/backend/replication/logical/snapbuild.c

src/backend/replication/slot.c

src/backend/storage/buffer/bufmgr.c

src/backend/storage/ipc/dsm.c

src/backend/storage/ipc/procarray.c

src/backend/storage/ipc/shm_mq.c

src/bin/pg_dump/pg_dump.c

src/bin/pg_upgrade/pg_upgrade.c

src/bin/psql/print.c

src/include/c.h