remove minor warning void function cannot return
remove minor warning void function cannot return

[skip ci] we do not build minheadless vm by now

OpenSmalltalk/vm,OpenSmalltalk/vm,timfel/squeakvm,timfel/squeakvm,OpenSmalltalk/vm,timfel/squeakvm,timfel/squeakvm,timfel/squeakvm,OpenSmalltalk/vm,timfel/squeakvm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm,timfel/squeakvm,timfel/squeakvm