luci-app-statistics: support graph menu entries without corresponding labels

Properly render menu items for plugin instances that do not have a
corresponding label defined.

This allows for registering new graph pages solely by dropping files
into /usr/lib/lua/luci/statistics/rrdtool/definitions/

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

diff --git a/applications/luci-app-statistics/luasrc/controller/luci_statistics/luci_statistics.lua b/applications/luci-app-statistics/luasrc/controller/luci_statistics/luci_statistics.lua
index 1bc0714..443f20b 100644 (file)
--- a/applications/luci-app-statistics/luasrc/controller/luci_statistics/luci_statistics.lua
+++ b/applications/luci-app-statistics/luasrc/controller/luci_statistics/luci_statistics.lua
@@ -88,7 +88,7 @@ function index()
                        _entry(
                                { "admin", "statistics", "collectd", section, plugin },
                                cbi("luci_statistics/" .. plugin ),
-                               labels[plugin], j * 10
+                               labels[plugin] or plugin, j * 10
                        )
                end