usb: s3c-otg: Rename local headers to dwc2_*h

The driver is actually for the Designware DWC2 controller.
This patch renames the local header files to dwc2_*h and
adjusts the sources to use the new names.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/usb/gadget/s3c_udc_otg.c b/drivers/usb/gadget/s3c_udc_otg.c
index 9cb6849..0bff63f 100644
--- a/drivers/usb/gadget/s3c_udc_otg.c
+++ b/drivers/usb/gadget/s3c_udc_otg.c
@@ -32,8 +32,8 @@
 
 #include <asm/mach-types.h>
 
-#include "s3c_udc_otg_regs.h"
-#include "s3c_udc_otg_priv.h"
+#include "dwc2_udc_otg_regs.h"
+#include "dwc2_udc_otg_priv.h"
 #include <usb/lin_gadget_compat.h>
 
 /***********************************************************/