pgsql: Add appropriate text for SIGHUP parameters instead of just

Log Message:
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Add appropriate text for SIGHUP parameters instead of just removing it
like previous patch did.

Per note from Tom Lane

Modified Files:
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pgsql/doc/src/sgml:
config.sgml (r1.201 -> r1.202)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/config.sgml?r1=1.201&r2=1.202)