Fuchsia VMOs will be non-executable by default in the future (SEC-42),
so we'll need to use zx_vmo_replace_as_executable to make it possible
to map them into memory as executable. And in the mean time, this call
is a no-op.

SEC-42
TBR: mlippautz

Change-Id: I4521559b163519ded4afa6b55e99f983e38b1de5
Reviewed-on: https://chromium-review.googlesource.com/c/1281824Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Wez <wez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58804}