pgsql: Remove a space that incorrectly precedes a comma in the PL/pgSQL

Log Message:
-----------
Remove a space that incorrectly precedes a comma in the PL/pgSQL
documentation.

Michael Fuhr

Modified Files:
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pgsql/doc/src/sgml:
plpgsql.sgml (r1.82 -> r1.83)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/plpgsql.sgml.diff?r1=1.82&r2=1.83)