This was replaced with prepare/commit long before:
  commit 
f7784b8ec9b6a041fa828cfbe9012fe51933f5ac
  KVM: split kvm_arch_set_memory_region into prepare and commit
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
        return -EINVAL;
 }
 
-int kvm_arch_set_memory_region(struct kvm *kvm,
-                              struct kvm_userspace_memory_region *mem,
-                              struct kvm_memory_slot old,
-                              int user_alloc)
-{
-       return 0;
-}
-
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
                                   struct kvm_memory_slot *memslot,
                                   struct kvm_userspace_memory_region *mem,