gluon-ath9k-workaround: Announce how often the workaround has been triggered.

package/gluon-ath9k-workaround/files/lib/gluon/alfred/announce.d/network/ath9k_workaround_trigger

+function trigger_count ()
+  return tonumber(fs.readfile('/tmp/ath9k_workaround_trigger'))
+end
+
+local ok, value = pcall(trigger_count)
+if ok then
+  return value
+else
+  return 0
+end