onnxruntime

[java] Fix for OnnxTensor creation when passing in a ByteBuffer containing elements of a different type (#21774)

### Description
Fixes a bug where the buffer offset and position was incorrectly
computed if the user supplied a `ByteBuffer` to `createTensor` but set
the type of the tensor to something other than `INT8`. This would be
more common if the user was trying to load the initializers from a
serialized representation and didn't want to bother with the type
information (which is the case in #21321).

### Motivation and Context
Partial fix for #21321. The remainder of the fix is to add a helper
which allows users to load initializers out of an `onnx_data` file, but
that will require adding protobuf as a dependency for the Java API to
allow the parsing of an ONNX file separately from the native code. It
might be nicer to put that functionality into ORT's C API so it can
return the lengths & offsets of the initializers when provided with an
ONNX file containing external initializers. We hit this kind of thing in
Java more often than other languages as in Java models can be supplied
as classpath resources which we can easily read, but not materialize on
disk for the ORT native library to read.