LU-3027 clio: Do not shrink sublock at cancel

LU-3027 clio: Do not shrink sublock at cancel

Shrinking sublock at ldlm lock cancel time means whoever happened
to attach to this lock just before will reenqueue the wrong lock.

Test-Parameters: envdefinitions=SLOW=yes,ENABLE_QUOTA=yes  clientdistro=el6 serverdistro=el6 clientarch=x86_64  serverarch=x86_64 mdtcount=1  testlist=parallel-scale,parallel-scale-nfsv3,parallel-scale-nfsv4
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Jian Yu <jian.yu@intel.com>
Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: I599da98ce364ccf459b5b5f3b72550115972c456
Reviewed-on: http://review.whamcloud.com/7569
Reviewed-by: Patrick Farrell <paf@cray.com>
Tested-by: Hudson
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>