PR #13411: [XLA:GPU][Allow cuda async allocator to use non-default pool
PR #13411: [XLA:GPU][Allow cuda async allocator to use non-default pool

Imported from GitHub PR https://github.com/openxla/xla/pull/13411

This patch allows user to construct the GpuCudaMallocAsyncAllocator to use the non-default memory pool, this is required if we want the allocator to just allocate for a particular memory space allocations, without the interference allocation requests from other memory space.  E.g, using a separate memory pool for XLA temp buffers will make the allocated temp buffer address stabled. 


Copybara import of the project:

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6a0fe3dd36790fc11eeb23cb954ac53435ed8897 by Shawn Wang <shawnw@nvidia.com>:

Allow cuda async allocator to use non-default pool

Merging this change closes #13411

FUTURE_COPYBARA_INTEGRATE_REVIEW=https://github.com/openxla/xla/pull/13411 from shawnwang18:shawnw/cuda_async_allocator_with_new_pool 6a0fe3dd36790fc11eeb23cb954ac53435ed8897
