MIPS: KVM: Mark KVM_GUEST (T&E KVM) as BROKEN_ON_SMP

MIPS: KVM: Mark KVM_GUEST (T&E KVM) as BROKEN_ON_SMP

Make KVM_GUEST depend on BROKEN_ON_SMP so that it cannot be enabled with
SMP.

SMP kernels use ll/sc instructions for an atomic section in the tlb fill
handler, with a tlbp instruction contained in the middle. This cannot be
emulated with trap & emulate KVM because the tlbp instruction traps and
the eret to return to the guest code clears the LLbit which makes the sc
instruction always fail.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/5588/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>