[PATCH 2/5] x86: Remove catomic_* locking primitives

[Wilco Dijkstra]

Hi Uros,

> > x86 didn't define __arch_c_compare_and_exchange_bool_* primitives

> The referred CMP is simply due to x86 not declaring
> catomic_compare_and_exchange_bool_acq primitive.

These catomic and __arch_c_ primitives are not used anymore - see [1] which
removes the last few cases. Also see [2] which switches atomics to compiler
builtins. Next we can use builtin atomics for compare_and_exchange_val/bool
and the fences - we no longer need any assembly code (or any target specific
code) for atomics.

Cheers,
Wilco

[1] https://sourceware.org/pipermail/libc-alpha/2025-September/169698.html
[2] https://sourceware.org/pipermail/libc-alpha/2025-September/169877.html