Обсуждение: pgsql: Add missing extern keyword for a couple of numutils functions

Add missing extern keyword for a couple of numutils functions

In passing, also remove a few surplus empty lines from pg_ltoa and
pg_ulltoa_n in numutils.c

Reported-by: Andrew Gierth
Discussion: https://postgr.es/m/87y2ou3xuh.fsf@news-spur.riddles.org.uk
Backpatch-through: 13, where these changes were introduced

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/095f2d95c92704747d84d499a33b527af42bb08e

Modified Files
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src/backend/utils/adt/numutils.c | 2 --
src/include/utils/builtins.h     | 4 ++--
2 files changed, 2 insertions(+), 4 deletions(-)