Sysfs files are not world writable. Allowing only root to write to sysfs files to keep non-privileged process from change the power policy. CRs-Fixed: 327239 Change-Id: Ibe44e888c28f854996c8a4391d99fdb7e0edd602 Signed-off-by: Praveena Pachipulusu <pveena@codeaurora.org>