Remove junk left from DSSSL to XSL conversion

doc/src/sgml/Makefile

@@ -300,7 +300,7 @@ endif # sqlmansectnum != 7
 
 # tabs are harmless, but it is best to avoid them in SGML files
 check-tabs:
-	@( ! grep '	' $(wildcard $(srcdir)/*.sgml $(srcdir)/ref/*.sgml $(srcdir)/*.dsl $(srcdir)/*.xsl) ) || (echo "Tabs appear in SGML/XML files" 1>&2;  exit 1)
+	@( ! grep '	' $(wildcard $(srcdir)/*.sgml $(srcdir)/ref/*.sgml $(srcdir)/*.xsl) ) || (echo "Tabs appear in SGML/XML files" 1>&2;  exit 1)
 
 ##
 ## Clean
@@ -308,7 +308,7 @@ check-tabs:
 
 # This allows removing some files from the distribution tarballs while
 # keeping the dependencies satisfied.
-.SECONDARY: postgres.xml $(GENERATED_SGML) HTML.index
+.SECONDARY: postgres.xml $(GENERATED_SGML)
 .SECONDARY: INSTALL.html INSTALL.xml
 .SECONDARY: postgres-A4.fo postgres-US.fo