[compiler-rt] [scudo] Move ALWAYS_INLINE up in tsd_shared's ScopedTSD ctor (PR #81982)

[via llvm-commits]

ChiaHungDuan wrote:

It's better to mention that's the micro benchmarks on Fuchsia so that we will know more context when look back. 

BTW, let's do the change for tsd_exclusive as well

https://github.com/llvm/llvm-project/pull/81982