pgsql: Fix obsolete description of -h option, per Andreas Schmidt.

Log Message:
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Fix obsolete description of -h option, per Andreas Schmidt.

Tags:
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REL8_1_STABLE

Modified Files:
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pgsql/doc/src/sgml/ref:
postmaster.sgml (r1.53 -> r1.53.6.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/postmaster.sgml.diff?r1=1.53&r2=1.53.6.1)