[compiler-rt] [sanitizer] Remove GetCurrentThread nullness checks from Allocate (PR #102828)

[Fangrui Song via llvm-commits]

MaskRay wrote:

> Have you tried to run out large set of internal tests?

Finished the large set of tests. The results (with a lot of noise) look good

https://github.com/llvm/llvm-project/pull/102828