habanalabs: add missing kernel-doc comments for hl_device fields

Add missing kernel-doc comments for the "last_error" and
"stream_master_qid_arr" fields of the "hl_device" structure".

Signed-off-by: Tomer Tayar <ttayar@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>