staging/lustre/llite: Move all remaining procfs entries to debugfs

This moves all remaining procfs handling in llite layer to debugfs.

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>