LU-13817 quota: print error when pool is absent

LU-13817 quota: print error when pool is absent

Print error for "lfs quota --pool" and
"lfs setquota -o" if pool is absent.

HPE-bug-id: LUS-9112
Test-Parameters: trivial testlist=sanity-quota
Change-Id: I4c2aa41d8c6f27742e68dfdc78c9d9365c760237
Signed-off-by: Sergey Cheremencev <sergey.cheremencev@hpe.com>
Reviewed-on: https://review.whamcloud.com/39505
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Emoly Liu <emoly@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>