RTEMS | GCC 14 Missing Atomic Support Routines for Older Cores (#5267)

[Joel Sherrill (@joel)]

Joel Sherrill created an issue: https://gitlab.rtems.org/rtems/rtos/rtems/-/issues/5267

Assignee: Joel Sherrill

## Summary
With GCC 14, it is not explicitly clear that GCC does not have the required atomics helper for older cores without atomic instructions. I first spotted this on the [uC5282](https://gitlab.rtems.org/rtems/rtos/rtems/-/issues/5230) but we did not realise this was a pervasive problem with over 30 BSPs across 7 target architectures.  The error generated is when linking `spcxx01`:

```
[4381/4381] Linking build/arm/rtl22xx/testsuites/samples/paranoia.exe
/home/joel/rtems-work/tools/next-gcc14/bin/../lib/gcc/arm-rtems7/14.3.0/../../../../arm-rtems7/bin/ld: testsuites/sptests/spcxx01/init.cc.707.o: in function `std::atomic_flag::test_and_set(std::memory_order)':
/home/joel/rtems-work/tools/next-gcc14/lib/gcc/arm-rtems7/14.3.0/include/c++/bits/atomic_base.h:226:(.text.Init+0x1b0): undefined reference to `__atomic_test_and_set' 
```

@opticron suggested that it did not matter where this routine was implemented, only that it was available when compiling for that BSP. This undefined function (___atomic_test_and_set_) has a well defined [interface](https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html). Providing this for the impacted BSPs is straightforward. The function is small and it only needs to be added to the YAML files for the BSP variants impacted.

This is the list of BSPs impacted:

- arm - csb336, csb337, csb637, edb7312, gumstix, kit637_v6, lpc24xx_ea, lpc24xx_ncs_ram, lpc24xx_ncs_rom_ext, lpc24xx_ncs_rom_int, lpc24xx_plx800_ram, lpc24xx_plx800_rom_int, lpc32xx_mzx, lpc32xx_mzx_stage_1, lpc32xx_mzx_stage_2, lpc32xx_phycore, rtl22xx, rtl22xx_t, smdk2410
- m68k - av5282, mcf5329
- mips - jmr3904
- moxie - moxiesim
- nios2 - nios2_iss
- riscv - grv32i, grv32im, niosvc10lp, noel32im, rv32i, rv32im,
- sparc - ut699

Some of these are likely candidates for deprecation in 7. But this issue should not be the only factor in that decision. It seems obvious that the RISC-V and SPARC BSPs listed are unlikely candidates for removal. 

@opticron and I compiled this list of impacted cores/ISAs found in the above BSPs:

- ARM: arm920, arm920t, arm7tdmi, arm7tdmi-s, xscale, arm926ej-s
- m68k: Coldfire ISA A
- MIPS: arch=3900
- Moxie: only one
- NIOS2: only one
- RISC-V: multiple single core (non-SMP)
- SPARC: ut699

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