fix: Ubuntu 21.10 and 20.xx

[shigechika]

If this Pull Request is work in progress, Add a prefix of “[WIP]” in the title.

What did you implement:

• fix WARN

% vuls report
[Oct 18 13:05:51]  INFO [localhost] vuls-v0.18.1-build-20211013_134621_8659668
[Oct 18 13:05:51]  WARN [localhost] Ubuntu 21.10 is not supported yet

• add linux-generic in ubuntu 20.xx kernel name list. this will be correcting reboot required message.

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context.

Fixes #1214

Type of change

Please delete options that are not relevant.

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce.

Checklist:

You don't have to satisfy all of the following.

• [ ] Write tests
• [ ] Write documentation
• [x] Check that there aren't other open pull requests for the same issue/feature
• [x] Format your source code by make fmt
• [ ] Pass the test by make test
• [ ] Provide verification config / commands
• [ ] Enable "Allow edits from maintainers" for this PR
• [ ] Update the messages below

Is this ready for review?: NO

Reference

• https://blog.github.com/2015-01-21-how-to-write-the-perfect-pull-request/

[JulianNeuhaus27]

@kotakanbe Can you have a look. The scanns for our Ubuntu 20.04 are effected by this, so I give a 👍 to get this in the next release 🙂