DOC: configuration.txt: add default_value for table_idle signature
table_idle converter takes optional default_value argument.
The documentation correctly describes this usage but <default_value> was
missing in the converter signature.
It should be backported with bbeec37b3 ("MINOR: stick-table:
Add table_expire() and table_idle() new converters")
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 5b4a5a4..98a85bd 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -17965,7 +17965,7 @@
period configured in the table. See also the sc_http_req_rate sample fetch
keyword.
-table_idle(<table>)
+table_idle(<table>,[,<default_value>])
Uses the input sample to perform a look up in the specified table. If the key
is not found in the table, the converter fails except if <default_value> is
set: this makes the converter succeed and return <default_value>. If the key