coresight: etm4x: Fix issues on trcseqevr access

coresight: etm4x: Fix issues on trcseqevr access

The TRCSEQEVR(3) is reserved, using '@nrseqstate - 1' instead to avoid
accessing the reserved register.

Fixes: f188b5e76aae ("coresight: etm4x: Save/restore state across CPU low power states")
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Jonathan Zhou <jonathan.zhouwen@huawei.com>
[Fixed capital letter in title]
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200916191737.4001561-12-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>