xtensa: PMU: fix base address for the newer hardware

commit 687eb3c4 upstream.

With introduction of ERI access control in RG.0 base address of the PMU
unit registers has changed. Add support for the new PMU configuration.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>