cpufreq: use correct unit when verify cur freq

cpufreq: use correct unit when verify cur freq

cpufreq_verify_current_freq checks() if the frequency returned by
the hardware has a slight delta with the valid frequency value
last set and returns "policy->cur" if the delta is within "1 MHz".
In the comparison, "policy->cur" is in "kHz" but it's compared
against HZ_PER_MHZ. So, the comparison range becomes "1 GHz".

Fix this by comparing against KHZ_PER_MHZ instead of HZ_PER_MHZ.

Fixes: f55ae08c8987 ("cpufreq: Avoid unnecessary frequency updates due to mismatch")
Signed-off-by: Sanjay Chandrashekara <sanjayc@nvidia.com>
[ sumit gupta: Commit message update ]
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>