pgsql: Fix Perl code which had broken the Windows build

Fix Perl code which had broken the Windows build

The previous change wanted to avoid modifying $_ in grep, but the code
just made the change in a local variable and then lost it.  Rewrite the
code using a separate map and grep, which is clearer anyway.

Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4d33a7f2e714848ca7b5b7ef8e244eead078ca13

Modified Files
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src/tools/msvc/vcregress.pl | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)