qemu: Do not skip virCPUUpdateLive if priv->origCPU is set
    
    Even though we got both the original CPU (used for starting a domain)
    and the updated version (the CPU really provided by QEMU) during
    incoming migration, restore, or snapshot revert, we still need to update
    the CPU according to the data we got from the freshly started QEMU.
    Otherwise we don't know whether the CPU we got from QEMU matches the one
    before migration. We just need to keep the original CPU in
    priv->origCPU.
    
    Messed up by me in v3.4.0-58-g8e34f4781.
    
    Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
    Reviewed-by: Pavel Hrdina <phrdina@redhat.com>