Move all not-x86_64 architecture tests to dedicated directories

[janekmi]

Rationale

There is only a handful of tests which are ppc64-specific:

• obj_heap_state/TEST3
• obj_heap_state/TEST4
• obj_heap_state/TEST5
• obj_persist_count/TEST2
• obj_persist_count/TEST3
• pmempool_sync/TEST54
• pmempool_sync/TEST55
• util_poolset_size/TEST1
• util_poolset/TEST10
• util_poolset/TEST9

The existence of these tests next to not-ppc64 tests is confusing when trying to analyze whether all tests meant to be run were run. Moving these tests to a dedicated directory/directories will give a clear signal to the test log reader e.g. ppc64_obj_heap_state tests obviously not meant to be run in the x86_64 CI.

API Changes

None.