cpufreq: CPPC: Update FIE arch_freq_scale in ticks for non-PCC regs

Currently, the CPPC Frequency Invariance Engine (FIE) is invoked from the
scheduler tick but defers the update of arch_freq_scale to a separate
thread because cppc_get_perf_ctrs() would sleep if the CPC regs are in PCC.

However, this deferred update mechanism is unnecessary and introduces extra
overhead for non-PCC register spaces (e.g. System Memory or FFH), where
accessing the regs won't sleep and can be safely performed from the tick
context.

Furthermore, with the CPPC FIE registered, it throws repeated warnings of
"cppc_scale_freq_workfn: failed to read perf counters" on our platform with
the CPC regs in System Memory and a power-down idle state enabled.  That's
because the remote CPU can be in a power-down idle state, and reading its
perf counters returns 0.  Moving the FIE handling back to the scheduler
tick process makes the CPU handle its own perf counters, so it won't be
idle and the issue would be inherently solved.

To address the above issues, update arch_freq_scale directly in ticks for
non-PCC regs and keep the deferred update mechanism for PCC regs.

Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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