pgsql: Add comment on why we're passing a useless 'false' to the plper

Add comment on why we're passing a useless 'false' to the plperl function compiler.

It's for compatibility with modules like PostgreSQL::PLPerl::NYTProf.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=c73fe72e2735d20aa132640d8fab4e0eca1ced95

Modified Files
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src/pl/plperl/plperl.c | 7 ++++++-
1 files changed, 6 insertions(+), 1 deletions(-)