package/collectd: explicitly disable lua

lua plugin has been added in version 5.6.0 with
https://github.com/collectd/collectd/commit/023092323ca617c8ff95b1efd4a055c29b1aaa3b

Disabled it otherwise it'll be enabled if liblua is found

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/collectd/collectd.mk

@@ -15,7 +15,7 @@ COLLECTD_LICENSE_FILES = COPYING libltdl/COPYING.LIB
 # These require unmet dependencies, are fringe, pointless or deprecated
 COLLECTD_PLUGINS_DISABLE = \
 	amqp apple_sensors aquaero ascent barometer dbi dpdkstat email \
-	gmond grpc hddtemp intel_rdt ipmi java libvirt lpar lvm \
+	gmond grpc hddtemp intel_rdt ipmi java libvirt lpar lua lvm \
 	madwifi mbmon mic multimeter netapp notify_desktop numa \
 	nut onewire oracle perl pf pinba powerdns python redis routeros \
 	rrdcached sigrok tape target_v5upgrade teamspeak2 ted \