ACPI: CPPC: Change default error code and clean up debug messages in probe

Change the default error code returned by acpi_cppc_processor_probe()
from -EFAULT (which is completely inadequate) to -ENODATA and change
the debug messages printed by it to contain more information and be
more consistent.

While at it, format some white space to follow the coding style.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>