Pattern-match FP8 calls with input converts without scales.
Pattern-match FP8 calls with input converts without scales.

This change pattern matches the following into an FP8 cublasLT custom call

  dot(x.astype(jnp.float16), y.astype(jnp.float16))

We previously matched a version of this that also included scaling into a custom call.

  dot(x.astype(jnp.float16) * x_scale, y.astype(jnp.float16) * y_scale)

Now the scales are optional even when the inputs are cast to FP16. There is no particular reason to cast inputs to FP16 if there are no input scales, but at least one internal model does this.
