Upgrade devel/libatomic_ops from v7.6.8 to v7.6.10

• Eliminate 'my_chunk_ptr-AO_initial_heap out of bounds' cppcheck warning
• Fix 'AO_*_TS_T is not defined' compiler warnings (GCC-8)
• Fix 'duplicate symbol' error for test_malloc/stack with static libs (OS X)
• Workaround 'argument to function assert is always 1' cppcheck warnings