Fix capitalization mismatch in subsystem description

The allowed values of jacorb subsystem properties are currently displayed in capital letters (ON, OFF) while the description and default values show a different string (on, off):

"queue-wait" => {
"type" => STRING,
"description" => "Indicates whether requests that exceed the maximum queue size should wait or not . When disabled, a TRANSIENT exception is thrown if the queue is full.",
"expressions-allowed" => false,
"nillable" => true,
"default" => "off",
"allowed" => [
"OFF",
"ON"
],
"access-type" => "read-write",
"storage" => "configuration",
"restart-required" => "all-services"
},