libvirt.tests: add new case into virsh send-key command

Signed-off-by: Alex Jia <chuanchang.jia@gmail.com>
Using new method to setup iscsi device

The new method wrap dependency checking, iscsi target setup and login steps,
and set default values for all needed params.

Signed-off-by: Yanbing Du <ydu@redhat.com>
libvirt_scsi: Fix some bugs.

1) Use `EXAMPLE*` for disk device type.
2) Raise `TestNAError` when dependent `mkisofs` don't exists.
3) Cleanup image files after test.
4) Check partition first to skip before other disk image are
   created.

Signed-off-by: Hao Liu <hliu@redhat.com>
libvirt_pci_passthrough: only check parameters for the current case.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Merge pull request #289 from Hao-Liu/fix_libvirt_scsi

libvirt_scsi: Fix some bugs.
Merge pull request #288 from will-Do/replace_iscsi_setup

Using new method to setup iscsi device
Merge pull request #242 from chuanchang/sendkey_test

libvirt.tests: add new case into virsh send-key command
Merge pull request #301 from yangdongsheng/passthrough

libvirt_pci_passthrough: only check parameters for the current case.
vm_xml: Change according to vm_xml change

This is fixed to adapt changes in:
https://github.com/autotest/virt-test/pull/1790

Signed-off-by: Hao Liu <hliu@redhat.com>
Merge pull request #277 from Hao-Liu/fix_os_xml

vm_xml: Change according to vm_xml change
virsh.dumpxml: Add cases for --update-cpu option

Signed-off-by: Yanbing Du <ydu@redhat.com>