tsan: add a test for vector memory accesses

Add a basic test that checks races between vector/non-vector
read/write accesses of different sizes/offsets in different orders.
This gives coverage of __tsan_read/write16 callbacks.

Depends on D114591.

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D114592

GitOrigin-RevId: 5cac2b956bcf42495a2253443502fb73dbb43c3d
2 files changed