Description of problem:
When running virt-install --cdrom foo.iso --os-variant=fedoraX

where X is 10 or higher, virtio devices are used for network and block.  However, they should not be used for the cdrom device as cdrom needs to continue to be IDE even if virtio is used for hard disks/network.

virtio does not emulate cdroms so cdrom access with this configuration fails

Version-Release number of selected component (if applicable):
python-virtinst-0.500.0-1.fc11.noarch

How reproducible:
every time

Steps to Reproduce:
1. virt-install --name foo --ram 512 --cdrom=foo.iso --os-variant=fedora10 --nodisks
2. virsh start foo
3. 
  
Actual results:
Machine will fail to boot from foo.iso indicating error 0003 and inability to read the cdrom

Expected results:
Machine boots from bootable foo.iso

Additional info:
Running virt-install command above with fedora10 variant produces:
    <disk type='file' device='cdrom'>
      <driver name='qemu' type=''/>
      <source file='/var/lib/libvirt/images/node7-rhev-hypervisor.iso'/>
      <target dev='vda' bus='virtio'/>
      <readonly/>
    </disk>

Running virt-install command above with fedora9 variant produces:
    <disk type='file' device='cdrom'>
      <driver name='qemu' type=''/>
      <source file='/var/lib/libvirt/images/node7-rhev-hypervisor.iso'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
    </disk>

The vda device will not boot but the IDE device will.