Add AO_load primitives generalization based on CAS

Add AO_load primitives generalization based on CAS

* src/atomic_ops/generalize-small.template (AO_XSIZE_load_acquire,
AO_XSIZE_load, AO_XSIZE_load_read, AO_XSIZE_load_acquire_read,
AO_XSIZE_load_full, AO_XSIZE_load_dd_acquire_read,
AO_XSIZE_store_release, AO_XSIZE_store, AO_XSIZE_store_write,
AO_XSIZE_store_release_write, AO_XSIZE_store_full): Move primitive
down to be after CAS defintion section.
* src/atomic_ops/generalize-small.template (AO_XSIZE_load_read,
AO_XSIZE_load_full, AO_XSIZE_load_acquire, AO_XSIZE_load): Add
generalization template primitive based on CAS.
* src/atomic_ops/generalize-small.h: Regenerate.