LU-12436 lov: return error if cl_env_get fails

LU-12436 lov: return error if cl_env_get fails

When cl_env_get() fails with an error return the error.

Lustre-change: https://review.whamcloud.com/35229
Lustre-commit: a7997c836bbfe2a0674007f1c23b9593e596e0ba

Test-Parameters: trivial
Cray-bug-id: LUS-7310
Signed-off-by: Shaun Tancheff <stancheff@cray.com>
Change-Id: Ia065aeb142a772f4d620b84111af423e27c06b90
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/38360
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>