`getDescriptorFromTensorTuple` and `getMutDescriptorFromTensorTuple`
extract the tensor type from an `unrealized_conversion_cast` op that
serves as a workaround for missing 1:N dialect conversion support.
This commit changes these functions so that they explicitly receive the
tensor type as a function argument. This is in preparation of merging
the 1:1 and 1:N conversion drivers. The conversion patterns in this file
will soon start receiving multiple SSA values (`ValueRange`) from their
adaptors (instead of a single value that is the result of
`unrealized_conversion_cast`). It will no longer be possible to take the
tensor type from the `unrealized_conversion_cast` op. The
`unrealized_conversion_cast` workaround will disappear entirely.
This ensures the explicit value is generated (and not a load into the
values array). Note that actually not storing values array at all is
still TBD, this is just the very first step.
1. C++ enum is set through enum class LevelType : uint_64.
2. C enum is set through typedef uint_64 level_type. It is due to the
limitations in Windows build: setting enum width to ui64 is not
supported in C.
Separates actual transformation files from supporting utility files in
the transforms directory. Includes a bazel overlay fix for the build (as
well as a bit of cleanup of that file to be less verbose and more
flexible).
