KVM: emulate: fix harmless typo in MMX decoding

It was using the wrong member of the union.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2e8f0e6..b8dc78f 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1081,7 +1081,7 @@
 		if (ctxt->d & Mmx) {
 			op->type = OP_MM;
 			op->bytes = 8;
-			op->addr.xmm = ctxt->modrm_rm & 7;
+			op->addr.mm = ctxt->modrm_rm & 7;
 			return rc;
 		}
 		fetch_register_operand(op);