pgsql: Revert "Avoid creation of the free space map for small heap rela

Revert "Avoid creation of the free space map for small heap relations."

This reverts commit ac88d2962a96a9c7e83d5acfc28fe49a72812086.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a23676503b746b7f1588cd2ab0c60411032d32da

Modified Files
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contrib/pageinspect/expected/page.out | 77 +++++----
contrib/pageinspect/sql/page.sql | 33 ++--
doc/src/sgml/storage.sgml | 13 +-
src/backend/access/brin/brin.c | 2 +-
src/backend/access/brin/brin_pageops.c | 10 +-
src/backend/access/heap/hio.c | 47 ++---
src/backend/access/heap/vacuumlazy.c | 17 +-
src/backend/access/transam/xact.c | 14 --
src/backend/storage/freespace/README | 38 +----
src/backend/storage/freespace/freespace.c | 275 +-----------------------------
src/backend/storage/freespace/indexfsm.c | 6 +-
src/include/storage/freespace.h | 9 +-
src/test/regress/expected/fsm.out | 75 --------
src/test/regress/parallel_schedule | 6 -
src/test/regress/serial_schedule | 1 -
src/test/regress/sql/fsm.sql | 55 ------
16 files changed, 102 insertions(+), 576 deletions(-)