coresight: Don't reject unrecognized ETMv3 format attributes

coresight: Don't reject unrecognized ETMv3 format attributes

config isn't the only field, there are also config1, config2, etc.
Rejecting unrecognized attributes is therefore inconsistent as it wasn't
done for all fields. It was only necessary when we were directly
programming attr->config into ETMCR and didn't hide the unsupported
fields, but now it's not needed so remove it.

Reviewed-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Tested-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20251128-james-cs-syncfreq-v8-7-4d319764cc58@linaro.org