sepolicy: rename proc.uidcpupower to sys.uidcpupower

Rename proc.uidcpupower to sys.uidcpupower so system server can
read and set the property

Test: adb shell settings put global sys_uidcpupower 1
      verify via getprop sys.uidcpupower

Change-Id: I6b78e755a444f6dce048f06f053d3002aa060b64
1 file changed