[huf] Fix bug in fast C decoders

[huf] Fix bug in fast C decoders

The input bounds checks were buggy because they were only breaking from
the inner loop, not the outer loop. The fuzzers found this immediately.
The fix is to use `goto _out` instead of `break`.

This condition can happen on corrupted inputs.

I've benchmarked before and after on x86-64 and there were small changes
in performance, some positive, and some negative, and they end up about
balacing out.

Credit to  OSS-Fuzz