Reference types in function definitions signatures are not allowed to
refer to function types (this will change when we fully integrate the
typed function references proposal).

Bug: v8:7748
Change-Id: I2456b810f85e608c48a952ef9e64d7a8ff78892b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2231352
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68264}