virttest.libvirt_xml.vm_xml: Add support of change current vcpu

Support change current vcpu in set_vm_vcpus method, add new
current_vcpu XMLAttribute in VMXMLBase.

This will benefit vcpu hotplug for setting current vcpu first.

Signed-off-by: Wayne Sun <gsun@redhat.com>
libvirt.tests: Add virsh vcpucount test

The test works for domain state as "shut off" or "running", it check
vcpucount result after vcpu hotplug using setvcpus.

For setvcpus, include four valid options:
  --config
  --config --maximum
  --live
  --guest

For vcpucount options, restrict up to 2 options together, upstream libvirt
support more options combinations now (e.g. 3 options together or single
--maximum option), for backward support, only following options are
checked:
  None
  --config --active
  --config --maximum
  --live --active
  --live --maximum
  --current --active
  --current --maximum
  --guest

Signed-off-by: Wayne Sun <gsun@redhat.com>
virttest.virsh: Add virsh nodecpumap command

Add nodecpumap command and fixed two functions' params description

Signed-off-by: Wayne Sun <gsun@redhat.com>
libvirt: Add virsh nodecpumap command test

Signed-off-by: Wayne Sun <gsun@redhat.com>
libvirt: virsh_vcpucount: Change to virsh.vcpucount

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Updating rv_build_install.py to be more efficient

Signed-off-by: Swapna Krishnan (skrishna@redhat.com)
run: Add --run-dropin option

Add a run option that executes scripts on a directory
called dropin sequentially in the host, rather than
the guest. The option to run the mentioned tests in
the host will be added on a future series.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Add dropin test wrapper

virt test wrapper that actually runs the dropin script.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Add dropin directory

Directory that holds the dropin tests.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>