LU-3647 hsm: small fixes for HSM

LU-3647 hsm: small fixes for HSM

This patch includes the following fixes for HSM:
1. Redefine D_HSM. It was defined to D_TRACE;
2. Fix lu_ref for lease handle
3. User input verification to make sure the hur size is less than
MDS_MAXREQSIZE;

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: I6ae9af71b08cf38174b6b470ef1602966aab1805
Reviewed-on: http://review.whamcloud.com/7243
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Tested-by: Hudson
Reviewed-by: jacques-Charles Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>