pmem2_mem_ext TEST5,6

[osalyk]

Environment Information

• Platform: ACY

Please provide a reproduction of the bug:

https://github.com/pmem/pmdk/actions/runs/11898534398/job/33155251015#step:4:1093

Tests failed, but were skipped in previous runs.
https://github.com/pmem/pmdk/actions/runs/11872226030/job/33085690634#step:4:1121

[janekmi]

Despite the system supports movdir64b. The library when run under Valgrind reports movdir64b is not supported:

<libpmem2>: <4> [cpu.c:187 is_cpu_movdir64b_present] movdir64b not supported