PPC: KVM: Make NX bit available with magic page

Because old kernels enable the magic page and then choke on NXed trampoline
code we have to disable NX by default in KVM when we use the magic page.

However, since commit b18db0b8 we have successfully fixed that and can now
leave NX enabled, so tell the hypervisor about this.
Signed-off-by: NAlexander Graf <agraf@suse.de>

arch/powerpc/kernel/kvm.c

@@ -417,7 +417,7 @@ static void kvm_map_magic_page(void *data)
 	ulong out[8];
 
 	in[0] = KVM_MAGIC_PAGE;
-	in[1] = KVM_MAGIC_PAGE;
+	in[1] = KVM_MAGIC_PAGE | MAGIC_PAGE_FLAG_NOT_MAPPED_NX;
 
 	epapr_hypercall(in, out, KVM_HCALL_TOKEN(KVM_HC_PPC_MAP_MAGIC_PAGE));