[perfcompare] Add initial size comparison tool for recipe to invoke

Bug: IN-646
Test: tested via 'led' with recipe change, plus tested manually using:
  python garnet/bin/perfcompare/perfcompare.py compare_sizes out/x64/snapshots/system.snapshot out/x64/snapshots/system.snapshot

Change-Id: I791d470b2f3355629ce64d3e83c2284444213561
1 file changed