virttest.utils_net: Support multiqueue macvtap

This patch make autotest support multiqueue Macvtap

Signed-off-by: Yunping Zheng <yunzheng@redhat.com>
Add msix vectors support

Signed-off-by: Yunping Zheng <yunzheng@redhat.com>

Conflicts:
	virttest/qemu_vm.py
tests.nic_hotplug: make nic_hotplug support msix vectors

Support a nic with msix vertors

Signed-off-by: Yunping Zheng <yunzheng@redhat.com>
test.multi_queues_test : Add some tests for multi queues

This patch add some tests for multi queues.

Signed-off-by: Yunping Zheng <yunzheng@redhat.com>

Conflicts:
	tests/enable_mq.py