Avoid unaligned accesses (SIGBUG/BUS_ADRALN) in IRT.

Pointers in IrtEntry aren't currently aligned under 64 bit builds. But
unaligned atomic stores (store exclusive) do not work on arm64 (causes
SIGBUG/BUS_ADRALN). Fix CC collector crashes caused by this.

Bug: 12687968
Change-Id: I1d2f5376778a9a1e5cfea876f1f57d7a88ad5445
2 files changed