include/linux/phonedev.h: Remove unused header

The header file include/linux/phonedev.h does not seem to be used
anywhere. It was orphaned by 7326446c "Staging: remove telephony
drivers". Remove it.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/phonedev.h

-#ifndef __LINUX_PHONEDEV_H
-#define __LINUX_PHONEDEV_H
-
-#include <linux/types.h>
-
-#ifdef __KERNEL__
-
-#include <linux/poll.h>
-
-struct phone_device {
-	struct phone_device *next;
-	const struct file_operations *f_op;
-	int (*open) (struct phone_device *, struct file *);
-	int board;		/* Device private index */
-	int minor;
-};
-
-extern int phonedev_init(void);
-#define PHONE_MAJOR	100
-extern int phone_register_device(struct phone_device *, int unit);
-#define PHONE_UNIT_ANY	-1
-extern void phone_unregister_device(struct phone_device *);
-
-#endif
-#endif