[compiler-rt] [asan] Pass -falign-functions=16 when building on Windows (PR #154694)

[Peter Collingbourne via llvm-commits]

pcc wrote:

This will only work if the function following `__asan_on_error` is aligned to 16, so this doesn't really guarantee anything either.

`interceptors_win.cpp` also knows how to intercept hotpatchable functions, so maybe we should build the runtime with `/hotpatch` or `-fms-hotpatch`.

https://github.com/llvm/llvm-project/pull/154694