pgsql-server: Fix for adding \n for zero-length win32 read_pipe return

Log Message:
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Fix for adding \n for zero-length win32 read_pipe return

Modified Files:
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pgsql-server/src/port:
exec.c (r1.22 -> r1.23)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/port/exec.c.diff?r1=1.22&r2=1.23)