staging: vt6655: dpc.h: Replace C99 // comment by /* */

Replace C99 "//" comment by "/* */"
Signed-off-by: Veronika Kabatova <veronicca114@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vt6655/dpc.h

@@ -39,4 +39,4 @@ device_receive_frame(
 	PSRxDesc pCurrRD
 );
 
-#endif // __RXTX_H__
+#endif /* __RXTX_H__ */