init: change file owners of sysfs nodes min_vrefresh and
idle_delay_ms in order to grant permission for hwcomposer
Bug: 202567084
Test: use the following commands
adb shell "vndservice call Exynos.HWCService 1005 i32 0 i32 30"
adb shell "vndservice call Exynos.HWCService 1006 i32 0 i32 1000"
Change-Id: Ia072a9826402bdf23d2577b8dc7f82b5e4d903f6