libvirt: fix virsh_vcpupin test.

Since the output of virsh vcpupin command is changed, we need
to update the parsing function for it.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
libvirt-virsh: update vcpupin function.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
utils_test: Add two utils functions into utils_test.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
libvirt-tests: update virsh vcpupin test.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
libvirt.tests.vcpupin: Fix testcase name for virsh commands&pep8.

Signed-off-by: Yu Mingfei <yumingfei@cn.fujitsu.com>