The precise type is only used for validation. For code generation,
knowing the kind is more than enough. Hence, only store and pass the
ValueKind in Liftoff, and not the full ValueType.

R=manoskouk@chromium.org

Bug: v8:11477
Change-Id: Ia42c0fa419f75b508bd2f210c767b631e93d3398
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2707170
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72997}