Be sure to surround any arguments with double-quote

[dinosaure]

No description provided.

[hannesm]

so previous we used a space as separator, now it is surrounded by ". For the latter, aren't the " that could be present in each argument (passing e.g. 'foo"bar') now disturbing and need to be escaped?

I've no good idea how this is atm done on solo5 and xen? I'd appreciate if we have a clean story across the backends for argument passing (even it is "yyy is not supported" -- certainly there's a maximum length of arguments anyways).

Also, how does parse-argv (is this used everywhere?) behave in terms of escaping and quoting?

[hannesm]

Thanks for preparing this PR. 2 years later, we consolidated the mirage-bootvar implementations into a single repository and opam package: https://github.com/mirage/mirage-bootvar.

We try to be consistent across targets, thus any change to bootvars should be done for all targets that we support. If you like to push this further, please don't hesitate to open a PR at https://github.com/mirage/mirage-bootvar. This repository will be archived soon.