LU-8889 llite: replace memory allocation with ll_env usage

LU-8889 llite: replace memory allocation with ll_env usage

Replace memory allocation with ll_env usage in ll_file_read
like in other functions.

Change-Id: I44445ab80cc856f45271e0888ea2538d2a44cdeb
Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: https://review.whamcloud.com/24064
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>