[OpenMP][libomp] Fix tasking debug assert (#95823)

The debug assert is meant to check that the index is a valid which means
the runtime needs to check against the size of the array instead of the
number of threads. A free()-ed thread put back in the thread pool may
index into anywhere inside the task team's available array from 0 to
tt_max_threads potentially.

Fixes: #94260
GitOrigin-RevId: 2e57e6366677390110f5382894c8afeba8da7419
3 files changed