It needs xsltproc but fails to build

xsltproc mosquitto.conf.5.xml
warning: failed to load external entity /usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl
compilation error: file manpage.xsl line 3 element import
xsl:import : unable to load /usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl
compilation error: file mosquitto.conf.5.xml line 4 element refentry
xsltParseStylesheetProcess : document is not a stylesheet
make[1]: *** [Makefile:51: mosquitto.conf.5] Error 5