pgsql: Remove pg_atoi()

Remove pg_atoi()

The last caller was int2vectorin(), and having such a general function
for one user didn't seem useful, so just put the required parts inline
and remove the function.

Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/b239564c-cad0-b23e-c57e-166d883cb97d@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/73508475d69e90f98ebd9b7e1a5933a26a49c5e9

Modified Files
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src/backend/utils/adt/int.c      | 32 +++++++++++++--
src/backend/utils/adt/numutils.c | 88 ----------------------------------------
src/include/utils/builtins.h     |  1 -
3 files changed, 28 insertions(+), 93 deletions(-)