If a given firmware doesn't have a token to support query-cpu-stopped-state,
its not likely to change during the lifetime of the kernel.

Only print this information once, not once per secondary thread.

While here, make the line wrap grep friendly.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>