xl2tpd: rename netifd protocol handler to l2tpv2 to avoid clashes with l2tpv3

Signed-off-by: Steven Barth <steven@midlink.org>

net/xl2tpd/Makefile

@@ -65,7 +65,7 @@ define Package/xl2tpd/install
 	$(INSTALL_DATA) ./files/options.xl2tpd $(1)/etc/ppp/
 
 	$(INSTALL_DIR) $(1)/lib/netifd/proto
-	$(INSTALL_BIN) ./files/l2tp.sh $(1)/lib/netifd/proto
+	$(INSTALL_BIN) ./files/l2tpv2.sh $(1)/lib/netifd/proto
 endef
 
 $(eval $(call BuildPackage,xl2tpd))