udc: dfu: s3c_udc: Provide function to check if USB reset was asserted

New dfu_usb_get_reset() method is necessary to distinct two different
use cases of dfu-util program.
This method checks if the USB bus reset has been really performed after
DFU DETACH.

Without this function the previous DFU behavior is preserved.
Signed-off-by: NLukasz Majewski <l.majewski@samsung.com>

drivers/usb/gadget/s3c_udc_otg.c

@@ -149,6 +149,11 @@ struct s3c_usbotg_reg *reg;
 struct s3c_usbotg_phy *phy;
 static unsigned int usb_phy_ctrl;
 
+bool dfu_usb_get_reset(void)
+{
+	return !!(readl(&reg->gintsts) & INT_RESET);
+}
+
 void otg_phy_init(struct s3c_udc *dev)
 {
 	dev->pdata->phy_control(1);