This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
  <dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
  struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
   text    data     bss     dec     hex filename
5321639  858418  715768 6895825  6938d1 vmlinux
with patch series:
   text    data     bss     dec     hex filename
5320026  858418  715768 
		
	
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|---|---|---|
| .. | ||
| configfs_internal.h | ||
| dir.c | ||
| file.c | ||
| inode.c | ||
| item.c | ||
| Makefile | ||
| mount.c | ||
| symlink.c | ||