Log Message:
-----------
Improve SGML build rules for non-HTML output, per Peter.
Modified Files:
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pgsql/doc/src/sgml:
Makefile (r1.89 -> r1.90)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/Makefile.diff?r1=1.89&r2=1.90)