pgsql: Improve comment about ignoring 128 error code on Windows:

Improve comment about ignoring 128 error code on Windows:

     * Microsoft reports it is related to mutex failure:
     *   http://archives.postgresql.org/pgsql-hackers/2010-09/msg00790.php

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=23177114c6f4f12d313d453e9153daf80c94c70b

Modified Files
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src/backend/postmaster/postmaster.c |    2 ++
1 files changed, 2 insertions(+), 0 deletions(-)