fs/char_dev.c: remove unused cdev_index()

Commit 66fa12c571d3 ("ieee1394: remove the old IEEE 1394 driver stack")
eliminated the only user of cdev_index(). So it can be removed too.

Signed-off-by: Namhyung Kim <[e-mail]>
Cc: Stefan Richter <[e-mail]>
Cc: Theodore Ts'o <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/char_dev.c

···
 	return ret;
 }
 
-int cdev_index(struct inode *inode)
-{
-	int idx;
-	struct kobject *kobj;
-
-	kobj = kobj_lookup(cdev_map, inode->i_rdev, &idx);
-	if (!kobj)
-		return -1;
-	kobject_put(kobj);
-	return idx;
-}
-
 void cd_forget(struct inode *inode)
 {
 	spin_lock(&cdev_lock);
···
 EXPORT_SYMBOL(cdev_alloc);
 EXPORT_SYMBOL(cdev_del);
 EXPORT_SYMBOL(cdev_add);
-EXPORT_SYMBOL(cdev_index);
 EXPORT_SYMBOL(__register_chrdev);
 EXPORT_SYMBOL(__unregister_chrdev);
 EXPORT_SYMBOL(directly_mappable_cdev_bdi);

include/linux/cdev.h

···
 
 void cdev_del(struct cdev *);
 
-int cdev_index(struct inode *inode);
-
 void cd_forget(struct inode *);
 
 extern struct backing_dev_info directly_mappable_cdev_bdi;