HID: hid-logitech-dj: querying_devices was never set

Set querying_devices flag to true when we start the enumeration
process.

This was missing from the original patch. It never produced
undesirable effects as it is highly improbable to have a second
enumeration triggered while a first one was still in progress.
Signed-off-by: NNestor Lopez Casado <nlopezcasad@logitech.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/hid/hid-logitech-dj.c

@@ -488,6 +488,8 @@ static int logi_dj_recv_query_paired_devices(struct dj_receiver_dev *djrcv_dev)
 	if (djrcv_dev->querying_devices)
 		return 0;
 
+	djrcv_dev->querying_devices = true;
+
 	dj_report = kzalloc(sizeof(struct dj_report), GFP_KERNEL);
 	if (!dj_report)
 		return -ENOMEM;