[v3] "returned TLS index was too high" due to incorrect interpretation of TlsAlloc return value

[NarutoUA]

Branch: main3

On my machine, mimalloc initialization fails with error returned TLS index was too high (1027002)

Based on mi_win_tls_slot_alloc, TlsAlloc return value is treated as index to zero-based array, despite Microsoft Docs tells you the opposite:

The value of the TLS index should be treated as an opaque value; do not assume that it is an index into a zero-based array.

[NarutoUA]

I had my application added to "Application Verifier" with TLS checks enabled, which made TlsAlloc return huge value.