include: Makefile_am: force symlink creation

Force symlink creation.  In the event, the daemon is being built and
installed when already present, should force creation of symlinks and
not fail on this case.

Change-Id: Ic2cf84c36422a3be208a18a07daacfc6c587162b
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/include/Makefile.am b/include/Makefile.am
index 50bb399..50f54d0 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -10,10 +10,10 @@
 # For now they will be the same during migration
 install-data-local:
 	$(MKDIR_P) $(DESTDIR)$(includedir)/host-ipmid
-	$(LN_S) ../ipmid/iana.hpp $(DESTDIR)$(includedir)/host-ipmid/iana.hpp
-	$(LN_S) ../ipmid/api.h $(DESTDIR)$(includedir)/host-ipmid/ipmid-api.h
-	$(LN_S) ../ipmid/oemopenbmc.hpp $(DESTDIR)$(includedir)/host-ipmid/oemopenbmc.hpp
-	$(LN_S) ../ipmid/oemrouter.hpp $(DESTDIR)$(includedir)/host-ipmid/oemrouter.hpp
-	$(LN_S) ../ipmid-host/cmd.hpp $(DESTDIR)$(includedir)/host-ipmid/ipmid-host-cmd.hpp
-	$(LN_S) ../ipmid-host/cmd-utils.hpp $(DESTDIR)$(includedir)/host-ipmid/ipmid-host-cmd-utils.hpp
+	$(LN_S) -f ../ipmid/iana.hpp $(DESTDIR)$(includedir)/host-ipmid/iana.hpp
+	$(LN_S) -f ../ipmid/api.h $(DESTDIR)$(includedir)/host-ipmid/ipmid-api.h
+	$(LN_S) -f ../ipmid/oemopenbmc.hpp $(DESTDIR)$(includedir)/host-ipmid/oemopenbmc.hpp
+	$(LN_S) -f ../ipmid/oemrouter.hpp $(DESTDIR)$(includedir)/host-ipmid/oemrouter.hpp
+	$(LN_S) -f ../ipmid-host/cmd.hpp $(DESTDIR)$(includedir)/host-ipmid/ipmid-host-cmd.hpp
+	$(LN_S) -f ../ipmid-host/cmd-utils.hpp $(DESTDIR)$(includedir)/host-ipmid/ipmid-host-cmd-utils.hpp