coresight: etm4x: Fix access to resource selector registers

coresight: etm4x: Fix access to resource selector registers

Resource selector pair 0 is always implemented and reserved. We must not
touch it, even during save/restore for CPU Idle. Rest of the driver is
well behaved. Fix the offending ones.

Reported-by: Yabin Cui <yabinc@google.com>
Fixes: f188b5e76aae ("coresight: etm4x: Save/restore state across CPU low power states")
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Yabin Cui <yabinc@google.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20240412142702.2882478-5-suzuki.poulose@arm.com