usb: configfs: synchronize the secure and udc_name state

The gadget driver unregister/probe is not allowed to reentry
for the same udc.

As the conditions for gadget driver unregister/probe entry,
gadget secure and udc_name status should be synchronized.
Otherwise, in old implement code logic, there is still a chance
to fall into trouble of gadget driver unregister/probe reentry
for the same udc.

Change-Id: I6eb30a36eab84afd656f5bee9678e8d44933c6bc
Signed-off-by: Yonghua Yan <yanyh2@motorola.com>
Reviewed-on: https://gerrit.mot.com/1287442
SLTApproved: Slta Waiver
SME-Granted: SME Approvals Granted
Tested-by: Jira Key
Reviewed-by: Yuecai Liu <liuyc20@motorola.com>
Reviewed-by: Jianqi Yang <yangj@motorola.com>
Submit-Approved: Jira Key
Reviewed-on: https://gerrit.mot.com/1338870
Reviewed-by: Huosheng Liao <liaohs@motorola.com>
Reviewed-on: https://gerrit.mot.com/1449122
Reviewed-on: https://gerrit.mot.com/1511640
Reviewed-by: Zonghua Liu <a17671@motorola.com>
Reviewed-by: Wang Wang <wangwang1@lenovo.com>

drivers/usb/gadget/configfs.c

@@ -1791,15 +1791,19 @@ static ssize_t secure_store(struct device *pdev, struct device_attribute *attr,
 	mode = !!mode;
 	if (mode == gi->secure)
 		return count;
+
+	mutex_lock(&gi->lock);
+
 	gi->secure = mode;
 
-	if (!gi->composite.gadget_driver.udc_name)
+	if (!gi->composite.gadget_driver.udc_name) {
+		mutex_unlock(&gi->lock);
 		return count;
+	}
 	pr_debug("Secure Store , UDC = %s, secure = %d\n",
 				gi->composite.gadget_driver.udc_name,
 				gi->secure);
 
-	mutex_lock(&gi->lock);
 	if (gi->secure) {
 		ret = usb_gadget_unregister_driver(
 				&gi->composite.gadget_driver);