ACPI: Remove repeated registered as cooling_device messages

This message shows up for each cpu.  Print as debug messages.

[   12.893967] processor ACPI0007:00: registered as cooling_device0
[   12.907838] processor ACPI0007:01: registered as cooling_device1

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: linux-acpi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>