xtensa: PMU: fix base address for the newer hardware

commit 687eb3c42f4ad81e7c947c50e2d865f692064291 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>