cpufreq: use proper units for frequency

cpufreq: use proper units for frequency

When I booted my RK3588 based system I noticed that cpufreq complained
about system clock:

[  +0.007211] cpufreq: cpufreq_online: CPU0: Running at unlisted initial frequency: 816000 KHz, changing to: 1008000 KHz

Then I realized that unit is displayed wrong: "KHz" instead of "kHz".

Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20240909095529.2325103-1-marcin.juszkiewicz@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>