Revert "Iterative move coalescing for gc regalloc"

There are lifetime issues with allocators and coloring
iterations that got flagged by valgrind.

This reverts commit 465ed699e810868fe5bb39730e6d149a4734372d.

Change-Id: I9e08172321af61d109c116a4f0742fa809e8094b
Test: m test-art-host
3 files changed