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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REL_12_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/d0747714e6ef193c16d1acf31c15f387877d591f
Modified Files
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src/tools/msvc/pgbison.pl | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)