This patch introduces the `MemorySpaceAttrInterface` interface. This
interface is responsible for handling the semantics of `ptr` operations.
For example, this interface can be used to create read-only memory
spaces, making any other operation other than a load a verification
error, see `TestConstMemorySpaceAttr` for a possible implementation of
this concept.
This patch also introduces Enum dependencies `AtomicOrdering`, and
`AtomicBinOp`, both enumerations are clones of the Enums with the same
name in the LLVM Dialect.
Also, see:
- [[RFC] `ptr` dialect & modularizing ptr ops in the LLVM
dialect](https://discourse.llvm.org/t/rfc-ptr-dialect-modularizing-ptr-ops-in-the-llvm-dialect/75142)
for rationale.
- https://github.com/llvm/llvm-project/pull/73057 for a prototype
implementation of the full change.
**Note: Ignore the first commit, that's being reviewed in
https://github.com/llvm/llvm-project/pull/86860 .**
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