Jit: Sapphire tuning - mostly scheduling.

Jit: Sapphire tuning - mostly scheduling.

Re-enabled load/store motion that had inadvertently been turned off for
non-armv7 targets.  Tagged memory references with the kind of memory
they touch (Dalvik frame, literal pool, heap) to enable more aggressive
load hoisting.  Eliminated some largely duplicate code in the target
specific files.  Reworked temp register allocation code to allocate next
temp round-robin (to improve scheduling opportunities).

Overall, nice gain for Sapphire.  Shows 5% to 15% on some benchmarks, and
measurable improvements for Passion.