Update arm64 Dockerfile to build audio support

[s-fairchild]

I would like to update the arm64 Dockerfile to support alsa.

Description

This is to update the arm64 Dockerfile to build alsa support.

Related Issue

https://github.com/mpromonet/v4l2rtspserver/issues/295

Motivation and Context

I use this project on some of my arm machines and rather than rebuilding the containers locally, I think it would be beneficial to have the upstream arm64 images support alsa.

It prevents users from rebuilding the arm64 docker images to support alsa.

Types of changes

• [ ] Docs change / refactoring / dependency upgrade
• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

[mpromonet]

Hi @s-fairchild

Thanks for the contribution.

Best Regards, Michel.