cpufreq: Return -EOPNOTSUPP if no policy supports boost

cpufreq: Return -EOPNOTSUPP if no policy supports boost

In cpufreq_boost_trigger_state(), if none of the the policies support
boost, policy_set_boost() will not be called and this function will
return 0.

But it is better to return an error to indicate that the platform
doesn't support boost.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
[ rjw: Subject and changelog edits ]
Link: https://patch.msgid.link/20251202072727.1368285-2-zhenglifeng1@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>