[mlir][linalg] Treat quant dialect type as unsupported in named conversion

Since the tosa-to-linalg conversion does not support the quant dialect type, we can treat it as unsupported instead of crash.  Issue was reported https://github.com/llvm/llvm-project/issues/62367

Reviewed By: springerm

Differential Revision: https://reviews.llvm.org/D151296