usb: dwc3: add disscramble quirk

This patch adds disscramble quirk, and it only needs to be enabled at fpga
board on some vendor platforms.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index f6ee623..56bada6 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -672,6 +672,7 @@
  * @setup_packet_pending: true when there's a Setup Packet in FIFO. Workaround
  * @start_config_issued: true when StartConfig command has been issued
  * @three_stage_setup: set if we perform a three phase setup
+ * @disable_scramble_quirk: set if we enable the disable scramble quirk
  */
 struct dwc3 {
 	struct usb_ctrlrequest	*ctrl_req;
@@ -776,6 +777,8 @@
 	unsigned		setup_packet_pending:1;
 	unsigned		start_config_issued:1;
 	unsigned		three_stage_setup:1;
+
+	unsigned		disable_scramble_quirk:1;
 };
 
 /* -------------------------------------------------------------------------- */