Fix tabbing in a Makefile - great testing ;-)

[[Imported from SVN: r5777]]

bin/duneproject

@@ -629,7 +629,7 @@ CLEANFILES = \$(PAGES)
 if ! BUILD_DOCS
 # add tag to notify that dist has been build without documentation
 dist-hook:
-        echo "# No documentation included in distribution! " > \$(distdir)/\$(DOCUMENTATION_TAG_FILE)
+	echo "# No documentation included in distribution! " > \$(distdir)/\$(DOCUMENTATION_TAG_FILE)
 endif
 
 include \$(top_srcdir)/am/global-rules