pgsql: Remove dynamic_shared_memory_type=none

Remove dynamic_shared_memory_type=none

PostgreSQL nowadays offers some kind of dynamic shared memory feature on
all supported platforms.  Having the choice of "none" prevents us from
relying on DSM in core features.  So this patch removes the choice of
"none".

Author: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bcbd940806a2011d6f99ae72ea5897e8a94c6093

Modified Files
--------------
doc/src/sgml/config.sgml                      |  6 +++---
doc/src/sgml/parallel.sgml                    |  8 --------
src/backend/access/transam/parallel.c         |  7 -------
src/backend/optimizer/plan/planner.c          |  4 +---
src/backend/storage/ipc/dsm.c                 | 15 ---------------
src/backend/storage/ipc/dsm_impl.c            |  3 ---
src/backend/utils/misc/postgresql.conf.sample |  1 -
src/bin/initdb/initdb.c                       | 20 +++++++++++++-------
src/include/storage/dsm_impl.h                |  1 -
9 files changed, 17 insertions(+), 48 deletions(-)