[tvm] Add support for int8 models, update TVM revision (#13519)
### Description
In the TVM EP, this adds more entries to the conversion from
`ONNXTensorElementDataType` to `DLDataType`. Additionally, it removes an
unused function and updates the TVM revision to allow running models
from recent revisions of TVM.
### Motivation and Context
In the TVM EP, the mapping from `ONNXTensorElementDataType` to
`DLDataType` was incomplete and neglected several integer types (in
particular `ONNX_TENSOR_ELEMENT_DATA_TYPE_UINT8` and
`ONNX_TENSOR_ELEMENT_DATA_TYPE_INT8`) which prevented some models from
running.
Co-authored-by: Peter Salas <psalas@octoml.ai>