usb: dwc2: gadget: don't embed ep0 buffers

When using DMA, data of the previous setup packet can be read back
from cache because ep0 and ctrl buffers are embedded in struct s3c_hsotg.
Allocate buffers instead of embedding them.

Tested-by: Robert Baldyga <r.baldyga@samsung.com>
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Reviewed-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 0d2ee29..7db83d0 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -434,6 +434,9 @@
 	u32 snpsid;
 };
 
+/* Size of control and EP0 buffers */
+#define DWC2_CTRL_BUFF_SIZE 8
+
 /**
  * struct dwc2_hsotg - Holds the state of the driver, including the non-periodic
  * and periodic schedules
@@ -684,8 +687,8 @@
 
 	struct usb_request *ep0_reply;
 	struct usb_request *ctrl_req;
-	u8 ep0_buff[8];
-	u8 ctrl_buff[8];
+	void *ep0_buff;
+	void *ctrl_buff;
 
 	struct usb_gadget gadget;
 	unsigned int enabled:1;