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/bcm_udc_otg_phy.c b/drivers/usb/gadget/bcm_udc_otg_phy.c
index c58388c..10b2e13 100644
--- a/drivers/usb/gadget/bcm_udc_otg_phy.c
+++ b/drivers/usb/gadget/bcm_udc_otg_phy.c
@@ -9,7 +9,7 @@
 #include <asm/io.h>
 #include <asm/arch/sysmap.h>
 
-#include "s3c_udc_otg_priv.h"
+#include "dwc2_udc_otg_priv.h"
 #include "bcm_udc_otg.h"
 
 void otg_phy_init(struct dwc2_udc *dev)