coresight: Handle helper enable failure properly

coresight: Handle helper enable failure properly

If a helper fails to be enabled, unwind any helpers that were already
enabled earlier in the loop. This avoids leaving partially enabled
helpers behind.

Fixes: 6148652807ba ("coresight: Enable and disable helper devices adjacent to the path")
Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Tested-by: James Clark <james.clark@linaro.org>
Tested-by: Jie Gan <jie.gan@oss.qualcomm.com>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20260515-arm_coresight_path_power_management_improvement-v14-2-f88c4a3ecfe9@arm.com