qemu.tests: cfg for checking clock offset after hotplug vcpu

Signed-off-by: Xu Tian <xutian@redhat.com>
qemu.tests: check kvm-clock using newer msr set

Signed-off-by: Xu Tian <xutian@redhat.com>
qemu.tests: cfg for kvm-clock newer msrs support check test

Signed-off-by: Xu Tian <xutian@redhat.com>