ACPI processor: remove spurious newline from warning message

Commit 4973b22a ("ACPI processor: reset the throttling state once it's
invalid") introduced a new warning which prints a spurious newline.

The ACPI_WARNING macro that is used already takes care of adding a
newline, after adding ACPI_CA_VERSION to the message. Remove the newline
to avoid the message getting split into two lines.

Signed-off-by: Frans Pop <elendil@planet.nl>
Signed-off-by: Len Brown <len.brown@intel.com>