Re: [libvirt] [PATCHv2 2/9] conf: move storage formats to common RNG file

We had incomplete RelaxNG support for storage formats listed in virstoragefile.h: commit 027bf2e added 'vdi' but forgot to update the <volume> and <domain> xml lists; the <volume> list was also missing 'fat' and 'vhd'. Maintaining two lists is a recipe for them getting out of sync, so make the list common so that both contexts benefit the next time we add a format in a single location. * docs/schemas/domaincommon.rng (storageFormat): Move... * docs/schemas/storagecommon.rng: ...here, and add vdi. * docs/schemas/storagevol.rng (formatfile): Use common list.