drivers/perf: hisi: UC PMU support statistics in power saving mode

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8LYGD


CVE: NA

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When the UC enable the power saving mode, the UC power management system
will turn off the counters register clock if the PMU is not enabled, and
we cannot write values to the counters register.

Set the UC PMU enable to turn on the clock, and then restore the UC PMU
configuration.

Signed-off-by: Junhao He <hejunhao3@huawei.com>