usb: dwc3: Remove current_trb as it is unused

This field was introduced but never used. So, remove it.
Signed-off-by: Amit Virdi <amit.virdi@st.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/core.h

@@ -431,7 +431,6 @@ struct dwc3_event_buffer {
  * @dwc: pointer to DWC controller
  * @saved_state: ep state saved during hibernation
  * @flags: endpoint flags (wedged, stalled, ...)
- * @current_trb: index of current used trb
  * @number: endpoint number (1 - 15)
  * @type: set to bmAttributes & USB_ENDPOINT_XFERTYPE_MASK
  * @resource_index: Resource transfer index
@@ -464,8 +463,6 @@ struct dwc3_ep {
 	/* This last one is specific to EP0 */
 #define DWC3_EP0_DIR_IN		(1 << 31)
 
-	unsigned		current_trb;
-
 	u8			number;
 	u8			type;
 	u8			resource_index;