[FEA] Remove deprecated functions and classes

[harrism]

After 24.04 we have a number of deprecated functions that can be removed in 24.06:

1. thrust_rmm_allocator.h can be removed as it contains a single deprecated class (this has actually been deprecated for 3 years! 51f04390791fc9d47b3155919edaecada36a2087)
2. Several deprecated functions in detail/aligned.hpp (they have moved to the non-detail file).
3. The ctor of cuda_async_memory_resource that uses thrust::optional (covered by #1535 )
4. The ctors of pool_memory_resource that takes an optional initial size.