[mlir][tensor] Add a tensor.concat operation (#72779)

This adds an operation for concatenating ranked tensors along a static
dimension, as well as a decomposition mirroring the existing lowering
from TOSA to Tensor. This offers a convergence point for "input" like
dialects that include various lowerings for concatenation operations,
easing later analysis. In the future, this op can implement the
necessary interfaces for tiling, as well as potentially add conversions
to some kind of linalg and/or memref counterpart.

This patch adds the op, the decomposition, and some basic
folding/canonicalization. Replacing lowerings with the op (such as the
TOSA lowering) will come as a follow up.

See
https://discourse.llvm.org/t/rfc-tensor-add-a-tensor-concatenate-operation/74858