This breaks the build on arm64. Untested diff below fixes it:

ld: error: undefined symbol: sev_encrypt_state
>>> referenced by vm.c
>>>               vm.o:(run_vm)

ld: error: undefined symbol: sev_launch_finalize
>>> referenced by vm.c
>>>               vm.o:(run_vm)

Index: arm64_vm.c
===================================================================
RCS file: /cvs/src/usr.sbin/vmd/arm64_vm.c,v
diff -u -p -r1.3 arm64_vm.c
--- arm64_vm.c	21 Sep 2024 04:12:18 -0000	1.3
+++ arm64_vm.c	4 Jun 2025 10:36:04 -0000
@@ -209,3 +209,19 @@ sev_encrypt_memory(struct vmd_vm *vm)
 	/* NOTREACHED */
 	return (-1);
 }
+
+int
+sev_encrypt_state(struct vmd_vm *vm, int vcpu_id)
+{
+	fatalx("%s: unimplemented", __func__);
+	/* NOTREACHED */
+	return (-1);
+}
+
+int
+sev_launch_finalize(struct vmd_vm *vm)
+{
+	fatalx("%s: unimplemented", __func__);
+	/* NOTREACHED */
+	return (-1);
+}