LU-8958 llite: remove llite_loop left overs

LU-8958 llite: remove llite_loop left overs

With the removal of llite_loop several pieces of code are still
present in the llite layer that were only used by the lloop device.
We can remove these no longer used pieces.

Lustre-change: https://review.whamcloud.com/26795
Lustre-commit: 2e875d5fc5b73f735bd42f5da54c23e4c2d35d5c

Change-Id: I67f2761ae29b8ba7bb3bc9bcc3e3f8ece73a3ea3
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: Minh Diep <minh.diep@intel.com>
Reviewed-on: https://review.whamcloud.com/28860
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>