[roll] Roll fuchsia [fidl][rust] Migrate EMPTY to default() in src/lib

This CL migrates FIDL table construction to use Default::default()
instead of ::EMPTY in: src/lib.

This is a continuation of I0c1e6ff00ad438bc65e9b6e7872ab4cbfc7563dc
which implemented Default for tables.

This change was automated by:

    fm() { fastmod --accept-all --extensions 'rs' "$@" -- src/lib; }
    fm '\.\.[a-zA-Z0-9:_-]+::EMPTY\b' '..Default::default()'
    fm '\b([a-zA-Z0-9:_-]+)::EMPTY\b' '$1::default()'
    # Undo false positive:
    git diff | grepdiff "BlockIndex" --output-matching=hunk | git apply -R
    fm -m '\b([a-zA-Z0-9:_-]+)\s*\{\s*\.\.Default::default\(\)\s*\}' '$1::default()'
    fx format-code

Original-Bug: 102876
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/846736
Original-Revision: 9b382313e9e85ea9804d34b37d8fc5eb29576366
GitOrigin-RevId: 59fd97cc6fc06b77b6cb45ead951726be8336b29
Change-Id: I746145190b17734377a87265dc84a6ae924ca0b5