The wasm call fuzzer is superseded by the wasm compile fuzzer, thus
remove it.

The chromium side will land in https://crrev.com/c/895531.

R=ahaas@chromium.org

Change-Id: I211d9f8ad2ca5432dbbc6ecce0b6e13760f1af60
Reviewed-on: https://chromium-review.googlesource.com/895534Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51034}