server,common : fix the GCC 12 stringop-overread false positive (again)

[angt]

Overview

Additional information

With

$ gcc --version
gcc (Ubuntu 12.4.0-5ubuntu1) 12.4.0
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

I got

      inlined from ‘common_speculative_impl_draft_simple::common_speculative_impl_draft_simple(const common_params_speculative&, uint32_t)’ at /home/angt/llamacpp/fixbuild/common/speculative.cpp:233:13:
  /usr/include/c++/12/bits/stl_algobase.h:434:30: error: ‘void* __builtin_memcpy(void*, const void*, long unsigned int)’ reading between 5 and 9223372036854775807 bytes from a region of size 4 [-Werror=stringop-overread]
    434 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
        |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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