USB: cdc-wdm: properly include types.h

The file include/uapi/linux/usb/cdc-wdm.h uses a __u16 so it needs to
include types.h as well to make the build system happy.

Fixes: 3edce1cf813a ("USB: cdc-wdm: implement IOCTL_WDM_MAX_COMMAND")
Cc: stable <stable@vger.kernel.org> # 3.10+
Cc: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/uapi/linux/usb/cdc-wdm.h b/include/uapi/linux/usb/cdc-wdm.h
index f03134f..0dc132e 100644
--- a/include/uapi/linux/usb/cdc-wdm.h
+++ b/include/uapi/linux/usb/cdc-wdm.h
@@ -9,6 +9,8 @@
 #ifndef _UAPI__LINUX_USB_CDC_WDM_H
 #define _UAPI__LINUX_USB_CDC_WDM_H
 
+#include <linux/types.h>
+
 /*
  * This IOCTL is used to retrieve the wMaxCommand for the device,
  * defining the message limit for both reading and writing.