Merge branch 'ps/gnumake-4.4-fix' into jch

Adjust Makefile for GNU make 4.4

* ps/gnumake-4.4-fix:
  Makefile: avoid multiple patterns when recipes generate one file

Documentation/Makefile

@@ -351,8 +351,16 @@ $(OBSOLETE_HTML): %.html : %.txto $(ASCIIDOC_DEPS)
 manpage-base-url.xsl: manpage-base-url.xsl.in
 	$(QUIET_GEN)sed "s|@@MAN_BASE_URL@@|$(MAN_BASE_URL)|" $< > $@
 
-%.1 %.5 %.7 : %.xml manpage-base-url.xsl $(wildcard manpage*.xsl)
-	$(QUIET_XMLTO)$(XMLTO) -m $(MANPAGE_XSL) $(XMLTO_EXTRA) man $<
+
+manpage-prereqs := manpage-base-url.xsl $(wildcard manpage*.xsl)
+manpage-cmd = $(QUIET_XMLTO)$(XMLTO) -m $(MANPAGE_XSL) $(XMLTO_EXTRA) man $<
+
+%.1 : %.xml $(manpage-prereqs)
+	$(manpage-cmd)
+%.5 : %.xml $(manpage-prereqs)
+	$(manpage-cmd)
+%.7 : %.xml $(manpage-prereqs)
+	$(manpage-cmd)
 
 %.xml : %.txt $(ASCIIDOC_DEPS)
 	$(QUIET_ASCIIDOC)$(TXT_TO_XML) -d manpage -o $@ $<