pgsql: Fix compiler warning induced by commit d8b15eeb8.

Fix compiler warning induced by commit d8b15eeb8.

I forgot that INT64_FORMAT can't be used with sscanf on Windows.
Use the same trick of sscanf'ing into a temp variable as we do in
some other places in zic.c.

The upstream IANA code avoids the portability problem by relying on
<inttypes.h>'s SCNdFAST64 macro.  Once we're requiring C99 in all
branches, we should do likewise and drop this set of diffs from
upstream.  For now, though, a hack seems fine, since we do not
actually care about leapseconds anyway.

Discussion: https://postgr.es/m/4e5d1a5b-143e-e70e-a99d-a3b01c1ae7c3@2ndquadrant.com

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/0d7066bc7f2010a4998f073690ea1eed2525fb60

Modified Files
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src/timezone/zic.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)