We add support for struct.get operation to the fuzzed module.
struct_get alternative is added to Generators
(i32, i64, f32, f64).

Bug: v8:11954
Change-Id: I85c03bb6ba896bff399eb1382fa42b0795ef65ed
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3081613Reviewed-by: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Rakhim Khismet <khismet@google.com>
Cr-Commit-Position: refs/heads/master@{#76191}