LU-5371 lmv: Do not ignore ENOENT in lmv_unlink

LU-5371 lmv: Do not ignore ENOENT in lmv_unlink

Return correct value (rc) in lmv_unlink. In lmv_unlink,
-ENOENT might be ingored for local directory unlink.

Change-Id: Ic839fe5d3da4d7e5d111608c73ca4b07b81a14e4
Signed-off-by: Wang Di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/11170
Tested-by: Jenkins
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>