Add opt-in for nucleo_f767zi firmwares

This partially reverts commit ce098756d79d8e4240bedc2bd74ff9a3a77fcedb.

The reverted commit dropped the build logic for all
nucleo_f767zi-related artifacts and thus for everything except the
native sim firmware.

Instead this commit reverts this change but comments out the
`update_image` and `factory_image` targets from the `artifacts` variable
in the top-level `meson.build`.

This allows to build these two targets explicitly with `ninja -C build
<target>` but does not include it into the deploy tar archive.

Since this archive is the only target of the project with
`build_by_default: true` this effectively disables the build with
minimal code changes.

0 files changed, 0 insertions, 0 deletions