fix #4957: add vendor and product information passthrough for SCSI-Disks

fix #4957: add vendor and product information passthrough for SCSI-Disks

adds vendor and product information for SCSI devices to the json schema
and checks in the VM create/update API call if it is possible to add
these to QEMU as a device option

Signed-off-by: Hannes Duerr <h.duerr@proxmox.com>
[FE: add missing space to exception message
     use config option for exception e.g. scsi0 rather than 'product'
     style fixes]
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>