make qemu-kvm replace qemu-kvm-spice

Now that qemu provides spice support, and qemu-kvm-spice is removed from
the archive, have qemu-kvm (which qemu-kvm-spice always depended on)
P/C/R qemu-kvm-spice.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>