staging: comedi: 8255.h: don't include "../comedidev.h"

The Comedi "8255.h" header doesn't use anything from "comedidev.h" apart
from `struct comedi_device` and `struct comedi_subdevice`, which are
only used to construct corresponding pointer types within the parameter
lists of function prototypes.  Just declare those structure types
incompletely and don't bother including "comedidev.h".
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/8255.h

@@ -19,8 +19,6 @@
 #ifndef _8255_H
 #define _8255_H
 
-#include "../comedidev.h"
-
 #define I8255_SIZE		0x04
 
 #define I8255_DATA_A_REG	0x00
@@ -35,6 +33,9 @@
 #define I8255_CTRL_A_MODE(x)	((x) << 5)
 #define I8255_CTRL_CW		(1 << 7)
 
+struct comedi_device;
+struct comedi_subdevice;
+
 int subdev_8255_init(struct comedi_device *, struct comedi_subdevice *,
 		     int (*io)(struct comedi_device *,
 			       int, int, int, unsigned long),