Report domaincaps <features><genid supported='yes'/> if the guest
config accepts <genid/> or <genid>$GUID</genid>.
Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
* Extract filling bhyve capabilities from virBhyveDomainCapsBuild()
into a new function virBhyveDomainCapsFill() to make testing
easier by not having to mock firmware directory listing and
hypervisor capabilities probing
* Also, just presence of the firmware files is not sufficient
to enable os.loader.supported, hypervisor should support UEFI
boot too
* Add tests to domaincapstest for the main caps possible flows:
- when UEFI bootrom is supported
- when video (fbus) is supported
- neither of above is supported
