LU-2836 tests: Re-enable sanity-quota/3,6 for ZFS

LU-2836 tests: Re-enable sanity-quota/3,6 for ZFS

Given the amount of fixes in Quota for ZFS 0.7.x and since Lustre 2.4.
Also ZFS backend is now not nearly as slow so sleep timeouts that work
for ldiskfs should also work for ZFS.
Re-enable these tests as they should consistantly pass now.

Test-Parameters: trivial
Test-Parameters: ostfilesystemtype=zfs mdtfilesystemtype=zfs ostcount=2 testlist=sanity-quota,sanity-quota,sanity-quota,sanity-quota,sanity-quota
Signed-off-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Change-Id: I23714181a1aada7a32a540853cb2e0bd9d7211a2
Reviewed-on: https://review.whamcloud.com/32956
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>