Add a boost to NNAPI DarwiNN HAL for better perf&power

See http://shortn/_X7vYHND2xN for testing with various NN models
faster execution of NNAPI results in less execution time and
in turn, less total power consumed.

Bug: 183576817
Test: adb push'd rc file to a device
      `cat /dev/cpuctl/nnapi-hal/cpu.uclamp.min` == 15.00
      ran MLPerf, got better scores

Change-Id: I398c3741fc46958f95a9b608a27b52da47c69597
1 file changed