PciAssignable: Make nic_name_re configurable.

nic_name_re used to filter nic name in host.

Signed-off-by: Feng Yang <fyang@redhat.com>
PciAssignable: Do not modprobe it, if self.driver is not available.

Signed-off-by: Feng Yang <fyang@redhat.com>
virttest.virt_vm: Simple wait_for_get_address() function

1) It broken our timeout mechanism.
2)The more important is we already have restart_gust_network() in wait_for_login(),
  so no need restart guest network in wait_for_get_address().
3) Could not get mac not always means we need restart guest network.

Signed-off-by: Feng Yang <fyang@redhat.com>
virttest.virt_vm: Do not call self.wait_for_get_address() in vm.login()

login() function is one time action. So it should not call wait_for_*()
function. Or we will have wait_for_* in wait_for_login().

Signed-off-by: Feng Yang <fyang@redhat.com>
virttest.virt_vm: Try to login again after restart network.

So will try to restart guest network when normal login timeout.
Call login again after restart guest network.
This is also what we want when adding restart_network code.
Please refer to (7dfcc5a0f9c3b9ca28f32490e89eda5216591649 in upstream)

Signed-off-by: Feng Yang <fyang@redhat.com>
Merge restart_guest_network() and renew_guest_ip() to restart_guest_network()

Signed-off-by: Feng Yang <fyang@redhat.com>
virttest.virt_vm: Try to get guest network status when login timeout in wait_for_login().

Signed-off-by: Feng Yang <fyang@redhat.com>
vm_xml: let delete device can also by device tag

In some situations, we don't care the device xml, so after this patch,
we can avoid generate device xml by set 'by_tag=True'.

Signed-off-by: Yanbing Du <ydu@redhat.com>
utils_test.libvirt: Fix parameter undefined error.

Signed-off-by: Yu Mingfei <yumingfei@cn.fujitsu.com>
vm_xml: Add memtune XML support and add 'unit' attribute for memory element

Signed-off-by: Yanbing Du <ydu@redhat.com>
Merge pull request #1848 from will-Do/memtune_xml

vm_xml: Add memtune XML support
Merge pull request #1852 from will-Do/del_device

vm_xml: let delete device can also by device tag
virttest/virsh.py: Add 'to_file' to capabilities func
Merge pull request #1859 from yumingfei/utils_test_fix

utils_test.libvirt: Fix parameter undefined error.
Merge pull request #1869 from PandaWei/capability

virttest/virsh.py: Add 'to_file' to capabilities func
Merge pull request #1722 from FengYang/PciAssignable

Two update for PciAssignable class
Merge pull request #1764 from FengYang/login

wait_for_login() related update
libvirt_xml: Add a function to delete memoryBacking tag.

del_memoryBacking_tag() can delete memoryBacking tag for specific vm,
and it's paired with add_memoryBacking_tag().