For update_lookuptable_tls: Adds a store-release to the lookuptable store and a load-acquire to the IBL generated code for both ARM and AArch64, as there is no lighter-weight way to ensure the mask and table stores are seen in the proper order.
For flushtime_global: made all readers and the increment use store-release semantics.
For safely_nullify_tables: leaving as weak stores since timing and ordering does not matter there.
Issue: #2502