nanobsd: Update fill_pkg.sh

[jlduran]

Summary

fill_pkg.sh is a script that links a package and its dependencies from a
"package dump" directory (like /usr/ports/packages/All) to a specified
directory (NANO_PACKAGE_DIR), for cust_pkgng()[*].

Update the script by:

• Using make package-name instead of make -V pkgname
• Looking for package files with *.pkg instead of *.txz
• Adding a -c option that copy the files instead of linking them[*]

• After 9af130ae8c03 cust_pkgng() cannot be used with a directory

populated by fill_pkg.sh, because it uses a nullfs mount, which don't
follow symlinks, therefore the links inside NANO_PACKAGE_DIR will not
work. I would prefer to just copy, and never symlink, but I leave this
decision to the reviewers.

PR: 269884

[imp]

These changes look good. thanks!

tools/tools/nanobsd/fill_pkg.sh

56

So I know this suggestion is a bigger change...

But we've started preferring $(foo) to foo where possible, and here it's completely possible.

The two should be nearly identical, and I think are for all the uses in this review.

So maybe as a separate commit later?

[jlduran]

tools/tools/nanobsd/fill_pkg.sh

56

Yes, I'm planning to propose a "shellcheck" commit at the end that catches all these suggestions. Thank you!