generated by two create/removes. One with file attibutes set, one without.
A dmapi destroy event should be generated in both cases, however PV960928
has shown that it may not be when attributes are not set.
Merge of master-melb:xfs-cmds:28771a by kenmcd.
test
Merge of master-melb:xfs-cmds:27847a by kenmcd.
changed _dmapi_scratch_mount to determine dmapi support by attempting to mount the filesystem with the dmapi mount option and checking it succeeds