pgsql: Remove bogus "extern" annotations on function definitions.

Remove bogus "extern" annotations on function definitions.

While this is not illegal C, project style is to put "extern" only on
declarations not definitions.

David Rowley

Discussion: https://postgr.es/m/CAKJS1f9RKLWXcMBQhvDYhmsMEo+ALuNgA-NE+AX5Uoke9DJ2Xg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/524d64ea8e3e49b4fda41ff9b2f048b697384058

Modified Files
--------------
contrib/postgres_fdw/deparse.c      | 4 ++--
contrib/postgres_fdw/postgres_fdw.c | 2 +-
src/backend/catalog/index.c         | 6 +++---
src/backend/catalog/partition.c     | 2 +-
src/backend/foreign/foreign.c       | 2 +-
src/backend/storage/ipc/shm_toc.c   | 6 +++---
src/backend/utils/adt/json.c        | 8 ++++----
7 files changed, 15 insertions(+), 15 deletions(-)