KVM: PPC: Book3S: Move little endian conflict to HV KVM

With the previous patches applied, we can now successfully use PR KVM on
little endian hosts which means we can now allow users to select it.

However, HV KVM still needs some work, so let's keep the kconfig conflict
on that one.

Signed-off-by: Alexander Graf <agraf@suse.de>

diff --cc arch/powerpc/kvm/Kconfig
Simple merge