Revert "cpufreq: governor: Use kobject release() method to free dbs_data"

This reverts commit a1964688 which is
commit a85ee640 upstream.

It breaks the Android kernel abi and is not needed for Android at this
point in time (this is an internal structure and no external kernel
modules should be using it, but it's in the abi signatures so something
went wrong somewhere.)

If this is needed in the future, it can be brought back in an ABI-safe
way.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I734bc4caef62a25fcf26a16665a73d24d249619c