pgsql: Remove now superfluous declarations of dlsym()ed symbols.

Remove now superfluous declarations of dlsym()ed symbols.

The prior commit declared them centrally.

Author: Andres Freund <andres@anarazel.de>
Reviewed-By: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20211101020311.av6hphdl6xbjbuif@alap3.anarazel.de

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/fd4bad1655391582f639527c325fc4a99680cc64

Modified Files
--------------
contrib/auth_delay/auth_delay.c                                | 2 --
contrib/auto_explain/auto_explain.c                            | 2 --
contrib/basebackup_to_shell/basebackup_to_shell.c              | 2 --
contrib/basic_archive/basic_archive.c                          | 3 ---
contrib/bloom/bloom.h                                          | 1 -
contrib/hstore_plperl/hstore_plperl.c                          | 2 --
contrib/hstore_plpython/hstore_plpython.c                      | 2 --
contrib/isn/isn.c                                              | 2 --
contrib/jsonb_plpython/jsonb_plpython.c                        | 2 --
contrib/ltree_plpython/ltree_plpython.c                        | 2 --
contrib/passwordcheck/passwordcheck.c                          | 2 --
contrib/pg_prewarm/autoprewarm.c                               | 1 -
contrib/pg_stat_statements/pg_stat_statements.c                | 2 --
contrib/pg_trgm/trgm_op.c                                      | 2 --
contrib/postgres_fdw/option.c                                  | 2 --
contrib/sepgsql/hooks.c                                        | 1 -
contrib/test_decoding/test_decoding.c                          | 4 ----
src/backend/replication/libpqwalreceiver/libpqwalreceiver.c    | 2 --
src/backend/replication/pgoutput/pgoutput.c                    | 2 --
src/pl/plperl/plperl.c                                         | 1 -
src/pl/plpgsql/src/plpgsql.h                                   | 5 -----
src/pl/plpython/plpy_main.c                                    | 2 --
src/pl/tcl/pltcl.c                                             | 1 -
src/test/modules/delay_execution/delay_execution.c             | 3 ---
src/test/modules/dummy_index_am/dummy_index_am.c               | 2 --
src/test/modules/dummy_seclabel/dummy_seclabel.c               | 3 ---
src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c | 2 --
src/test/modules/test_oat_hooks/test_oat_hooks.c               | 2 --
src/test/modules/test_rls_hooks/test_rls_hooks.c               | 2 --
src/test/modules/test_shm_mq/test.c                            | 2 --
src/test/modules/worker_spi/worker_spi.c                       | 1 -
31 files changed, 64 deletions(-)