[compiler-rt][Fuzzer] SetThreadName windows implementation new try. (#76761)

SetThreadDescription symbol needs to be dynamically loaded before usage.
Then using a wide string buffer, since we re using a null terminated
string, we can use MultiByteToWideChar -1 as 4th argument to finally set
the thread name.

Previously `SetThreadDescription` was called directly causing crash.
It was reverted in dd3aa26f