Fuzzers that exercise the SPIR-V reader are being moved to OSS-Fuzz.
This change removes them from the Chromium build so that they cease to
be run by ClusterFuzz. The change also applies a small refactoring to
the fuzzer build rules, so that the tint_ast_clone fuzzer is specified
together with other fuzzers that require the WGSL reader and writer.
Bug: chromium:1243084
Change-Id: I4f5d12a679366634c7cad3e7ac18075bb046a8ba
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/62800
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: Alastair Donaldson <afdx@google.com>