packages: add mdadm package for software RAID support

[tzneal]

Issue number:

Closes #

Description of changes:

Adds the mdadm package to support future software raid configuration of local ephemeral storage.

Testing done:

• Built/ran an AMI and used an admin container to run mdadm and configure local storage.
• cargo make check

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[bcressey]

Looks good overall.

As a general packaging note: udev rules and systemd units are places where unexpected dependencies can hide, so they're worth a close look.

[bcressey]

This file should be removed - it gets created if you accidentally run cargo make in a package directory.

[bcressey]

remove this Cargo.lock

[tzneal]

Without this, cargo make -e PACKAGE=mdadm build-package fails. What am I missing?

[larvacea]

Good question, and I too have this problem with cargo make build-package. It's not just you, and it's not just this package. I'll let you know as soon as I have an answer. Or, possibly, @bcressey will answer us both before I figure it out, as he does.

[larvacea]

Good news: thanks to @yeazelm I know when we introduced this misbehavior in our build system. The somewhat good news is that there is a workaround: if you build a variant that includes this package (e.g., you add it to the packages in the aws-dev variant and build that variant), the build system will happily build your package without a Cargo.lock file, as it builds the variant you have selected. I will see what we can do about making cargo make build-package work as intended, and update this pull request.