tsan: add more micro benchmarks

1. Add a set of micro benchmarks for memory accesses,
   mem* functions and unaligned accesses.
2. Add support for multiple benchmarks in a single binary
   (or it would require 12 new benchmark binaries).
3. Remove the "clock growth" machinery,
   it affects the current tsan runtime by increasing size of
   all vector clocks, but this won't be relevant for the new
   tsan runtime.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D106961