staging: comedi: comedi_usb.c: include new "comedi_usb.h" header

Include the new "comedi_usb.h" header instead of <linux/usb.h> and
"comedidev.h", which will now get included indirectly.
Signed-off-by: NIan Abbott <abbotti@mev.co.uk>
Reviewed-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/comedi_usb.c

@@ -17,9 +17,8 @@
  */
 
 #include <linux/module.h>
-#include <linux/usb.h>
 
-#include "comedidev.h"
+#include "comedi_usb.h"
 
 /**
  * comedi_to_usb_interface() - comedi_device pointer to usb_interface pointer.