Turn off deprecated bison warnings under MSVC
These are disabled by the configure code, so this is just fixing an
inconsistency in the MSVC code.
Backpatch to all live branches.
Branch
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REL9_6_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/80370836f7563653390065b225ece4305aba3d57
Modified Files
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src/tools/msvc/pgbison.pl | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)