HWASan support in ART.

Two small tweaks:
* The highest 8 bits of a pointer in hwasan contain a random tag which needs to
  be removed before comparing _unrelated_ pointers.
* Annotate DoLongJump. HWASan needs to re-tag the newly unallocated stack space
  to match SP. This is similar to ASan annotation (__asan_handle_noreturn), but
  more precise - HWASan needs to know the destination SP address because it can
  not conservatively "unpoison" the entire stack like ASan does.

Bug: 112438058
Test: mmm SANITIZE_TARGET=hwaddress

Change-Id: I9f9d92495b3a4b2637e48c7af1b614e8d1db8ea0
2 files changed