pgsql: Add comment that on Win32, we don't need to check the .pgpass

Log Message:
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Add comment that on Win32, we don't need to check the .pgpass file
permission, per Magnus.

Modified Files:
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pgsql/src/interfaces/libpq:
fe-connect.c (r1.343 -> r1.344)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-connect.c.diff?r1=1.343&r2=1.344)