devfreq: clip max/min frequencies in store APIs

devfreq: clip max/min frequencies in store APIs

In max_freq_store(), we allow any large to be
stored as max_freq
Similarly in min_freq_store() we allow any
lower value as min_freq

Fix this so that we clip max_freq to highest
freq value supported and clip min_freq to
lowest freq value supported

Bug 200260336

Change-Id: I6b11f6a5fd31f9411299dbeea1d3a528e1077bc5
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/1266463
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>