usb: s3c-otg: Rename USB_GADGET_S3C_UDC_OTG* to USB_GADGET_DWC2_OTG*

The s3c-otg IP block is in fact a DWC2 OTG one, so finally rename the
config option to make it less misleading. No functional change, just
a mechanical change done using the following script:

  git grep USB_GADGET_S3C_UDC_OTG | cut -d : -f 1 | sort -u | \
  while read line ; do
    sed -i "s/USB_GADGET_S3C_UDC_OTG/USB_GADGET_DWC2_OTG/g" $line ;
  done

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/include/configs/s5p_goni.h b/include/configs/s5p_goni.h
index 2877e19..8f65d7e 100644
--- a/include/configs/s5p_goni.h
+++ b/include/configs/s5p_goni.h
@@ -269,8 +269,8 @@
 
 #define CONFIG_SYS_MAX_I2C_BUS	7
 #define CONFIG_USB_GADGET
-#define CONFIG_USB_GADGET_S3C_UDC_OTG
-#define CONFIG_USB_GADGET_S3C_UDC_OTG_PHY
+#define CONFIG_USB_GADGET_DWC2_OTG
+#define CONFIG_USB_GADGET_DWC2_OTG_PHY
 #define CONFIG_USB_GADGET_DUALSPEED
 #define CONFIG_USB_GADGET_VBUS_DRAW 2
 #define CONFIG_CMD_USB_MASS_STORAGE