bugfix: created dir for zipkin. (#377) (#378)

diff --git a/Makefile b/Makefile
index 76ee316..2ac7952 100644
--- a/Makefile
+++ b/Makefile
@@ -98,6 +98,9 @@
 	$(INSTALL) -d $(INST_LUADIR)/apisix/lua/apisix/plugins/prometheus/
 	$(INSTALL) lua/apisix/plugins/prometheus/*.lua $(INST_LUADIR)/apisix/lua/apisix/plugins/prometheus/
 
+	$(INSTALL) -d $(INST_LUADIR)/apisix/lua/apisix/plugins/zipkin/
+	$(INSTALL) lua/apisix/plugins/zipkin/*.lua $(INST_LUADIR)/apisix/lua/apisix/plugins/zipkin/
+
 	$(INSTALL) -d $(INST_LUADIR)/apisix/lua/apisix/plugins
 	$(INSTALL) lua/apisix/plugins/*.lua $(INST_LUADIR)/apisix/lua/apisix/plugins/