add + for submake lines - needed by gmake for parallel building if $(MAKE) not used directly

--- Makefile.in.orig	2007-12-23 15:49:43 UTC
+++ Makefile.in
@@ -93,25 +93,25 @@ dependencies: dummy
 
 
 $(DOCSUBDIRS): dummy
-	for i in $(DOCSUBDIRS); do \
+	+for i in $(DOCSUBDIRS); do \
 	  (cd $$i; $(SUBMAKE) ) || exit 1; \
 	done
 
 
 $(DUMMYSUBDIRS):        dummy
-	for i in $(ALLSUBDIRS); do \
+	+for i in $(ALLSUBDIRS); do \
 	  (cd $$i; $(SUBMAKE) ) || exit 1; \
 	done
 
 
 install: dummy
-	for i in $(ALLSUBDIRS) $(DOCSUBDIRS); do \
+	+for i in $(ALLSUBDIRS) $(DOCSUBDIRS); do \
 	  (cd $$i; $(MAKE) install) || exit 1; \
 	done
 
 
 uninstall: dummy
-	for i in $(ALLSUBDIRS) $(DOCSUBDIRS); do \
+	+for i in $(ALLSUBDIRS) $(DOCSUBDIRS); do \
 	  (cd $$i; $(MAKE) uninstall) || exit 1; \
 	done
 	$(RM) -Rf $(datadir)/t1lib-$(t1lib_version).$(t1lib_revision)
@@ -127,10 +127,10 @@ uninstall: dummy
 
 
 clean: dummy
-	for i in $(ALLSUBDIRS); do \
+	+for i in $(ALLSUBDIRS); do \
 	  (cd $$i; $(MAKE) clean) || exit 1; \
 	done
-	for i in $(DOCSUBDIRS); do \
+	+for i in $(DOCSUBDIRS); do \
 	  (cd $$i; $(MAKE) clean) || exit 1; \
 	done