* doc/Makefile.am (dist_doc_DATA): Remove variable.
	(dist_html_DATA, dist_pdf_DATA): New variables.
	(MAINTAINERCLEANFILES):
	Remove $(TECHNICAL_HTML_OUTPUTS), $(TECHNICAL_PDF),
	$(TUTORIAL_HTML_OUTPUTS), $(TUTORIAL_PDF),
	$(WHITE_PAPER_HTML_OUTPUTS), $(WHITE_PAPER_PDF),
	$(REF_GUIDE_HTML_OUTPUTS), $(REF_GUIDE_PDF) and
	$(USER_REFMAN_PDF).
	Add $(dist_html_DATA) and $(dist_pdf_DATA).