cleanup(cmd): require kernelrelease and kernelversion from user in local command.

[FedeDP]

What type of PR is this?

/kind cleanup

Any specific area of the project related to this PR?

/area cmd

What this PR does / why we need it:

Require kernelrelease and eventually kernelversion to be passed by user instead of using unix. This allows driverkit to be portable (eg: building on windows).
Useful to fix falcosecurity/falcoctl#356 since falcoctl is built for windows and osx too and its deps must be portable.

It is a small UX worsening but since all driverkit commands already require kernelrelease, i think it is safe to do so for local too.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[FedeDP]

/cc @dwindsor 🚀

[FedeDP]

Most probably, as next step for the local builder, i would love to introduce back the capability to receive --kernelurls parameter and download them.
Here the hardest part would be to correctly extract and manage them since kernel headers packages can have different format on different distros and we have a single local builder template.
I think that the local builder processor can download kernelurls packages for us; then we might want to use eg: https://github.com/mholt/archiver to extract the kernel headers packages, no matters the format.

[EXONER4TED]

/approve

[poiana]

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