[COMMITTERS] pgsql: Further tweaks to compiler flags for PL/Perl on Windows.

Further tweaks to compiler flags for PL/Perl on Windows.

It now emerges that we can only rely on Perl to tell us we must use
-D_USE_32BIT_TIME_T if it's Perl 5.13.4 or later.  For older versions,
revert to our previous practice of assuming we need that symbol in
all 32-bit Windows builds.  This is not ideal, but inquiring into
which compiler version Perl was built with seems far too fragile.
In any case, we had not previously had complaints about these old
Perl versions, so let's assume this is Good Enough.  (It's still
better than the situation ante commit 5a5c2feca, in that at least
the effects are confined to PL/Perl rather than the whole PG build.)

Back-patch to all supported versions, like 5a5c2feca and predecessors.

Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/1d7a479d22f68c03d22c76b9a6de5cdf6ea9759b

Modified Files
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src/tools/msvc/Mkvcbuild.pm | 12 ++++++++++++
1 file changed, 12 insertions(+)