See
https://discourse.llvm.org/t/psa-opty-create-now-with-100-more-tab-complete/87339.

I plan to mark these as deprecated in
https://github.com/llvm/llvm-project/pull/164649.

The purpose of this patch is to allow converting FIR array representation to
memref when possible without hitting memref verifier issue.

The issue was that FIR arrays may be assumed size, in which case the
last dimension will not be known at runtime. Flang uses -1 to encode
this to fulfill Fortran 2023 standard requirements in 18.5.3 point 5
about CFI_desc_t.

When arrays are converted to memeref, if this `-1` reaches memeref
operations, it triggers verifier errors (even if the conversion happened
in code that guards the code to be entered at runtime if the array is
assumed-size because folders/verifiers do not take into account
reachability).

This follows-up on discussions in #163505 merge requests

Set the correct address space for constant variables. Address of
operation will introduce an address cast.

Do not issue call to _FortranACUFAllocDescriptor inside gpu module.

When the descriptor of a global device variable is re-materialized to be
passed to a kernel, make sure it is allocated in managed memory
otherwise the kernel launch will fail.

A prior PR added a portion of the global address space modifications
required for declare target to, this PR seeks to add
 a small amount more leftover from that PR.
   
The intent is to allow for more correct IR that the backends (in
particular AMDGPU) can treat more aptly for optimisations and code
correctness
    
1/3 required PRs to enable declare target to mapping, should look at PR
3/3 to check for full green passes (this one will fail a number due to
some dependencies).
    
Co-authored-by: Raghu Maddhipatla raghu.maddhipatla@amd.com

This patch introduces the `LLVMAddrSpaceAttrInterface` for defining
compatible LLVM address space attributes

To test this interface, this patch also adds:
- Adds NVVMMemorySpaceAttr implementing both LLVMAddrSpaceAttrInterface
and MemorySpaceAttrInterface
- Converts NVVM memory space constants from enum to MLIR enums
- Updates all NVVM memory space references to use new attribute system
- Adds support for NVVM memory spaces in ptr dialect translation

Example:
```mlir
llvm.func @nvvm_ptr_address_space(
    !ptr.ptr<#nvvm.memory_space<global>>,
    !ptr.ptr<#nvvm.memory_space<shared>>,
    !ptr.ptr<#nvvm.memory_space<constant>>,
    !ptr.ptr<#nvvm.memory_space<local>>,
    !ptr.ptr<#nvvm.memory_space<tensor>>,
    !ptr.ptr<#nvvm.memory_space<shared_cluster>>
  ) -> !ptr.ptr<#nvvm.memory_space<generic>>
```
Translating the above code to LLVM produces:
```llvm
declare ptr @nvvm_ptr_address_space(ptr addrspace(1), ptr addrspace(3), ptr addrspace(4), ptr addrspace(5), ptr addrspace(6), ptr addrspace(7))
```


To convert the memory space enum to the new enum class use:
```bash
grep -r . -e "NVVMMemorySpace::kGenericMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kGenericMemorySpace/NVVMMemorySpace::Generic/g"
grep -r . -e "NVVMMemorySpace::kGlobalMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kGlobalMemorySpace/NVVMMemorySpace::Global/g"
grep -r . -e "NVVMMemorySpace::kSharedMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kSharedMemorySpace/NVVMMemorySpace::Shared/g"
grep -r . -e "NVVMMemorySpace::kConstantMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kConstantMemorySpace/NVVMMemorySpace::Constant/g"
grep -r . -e "NVVMMemorySpace::kLocalMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kLocalMemorySpace/NVVMMemorySpace::Local/g"
grep -r . -e "NVVMMemorySpace::kTensorMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kTensorMemorySpace/NVVMMemorySpace::Tensor/g"
grep -r . -e "NVVMMemorySpace::kSharedClusterMemorySpace" -l | xargs sed -i -e "s/NVVMMemorySpace::kSharedClusterMemorySpace/NVVMMemorySpace::SharedCluster/g"
```

NOTE: A future patch will add support for ROCDL, it wasn't added here to
keep the patch small.