KVM: drive if pci id fix

- ide should be 00:00:01.1
- usb should be 00:00:01.2
- simplify logic in a template
- fix #39

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
Merge pull request #43 from miurahr/fix_kvm_pci_devnum

KVM: drive if pci id fix