[mlir][sparse] Use the runtime DimLevelType instead of a separate tablegen enum

This differential replaces all uses of SparseTensorEncodingAttr::DimLevelType with DimLevelType.  The next differential will break out a separate library for the DimLevelType enum, so that the Dialect code doesn't need to depend on the rest of the runtime

Depends On D135995

Reviewed By: aartbik

Differential Revision: https://reviews.llvm.org/D135996