power_key: adjust devfreq sysfs naming to linux 5.6
Linux changes the sysfs naming of devfreq from what we currently use, see https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=66d0e797bf095d407479c89952d42b1d96ef0a7f
Signed-off-by: Martin Kepplinger martin.kepplinger@puri.sm
Edited by Martin Kepplinger