Update vacant state in insert_node
Update vacant state in insert_node

Adding a new new node requires to update the vacant state of the focused
node's parent when the focus is itself vacant, otherwise we end up with
non-valid vacant states and windows will seem to be hidden.

JBouron/bspwm,XiKuuKy/bspwm,jbalint/bspwm,baskerville/bspwm,jbalint/bspwm,nfnty/bspwm,nfnty/bspwm,netzverweigerer/bspwm,ikn/bspwm,JBouron/bspwm,JBouron/bspwm,medisun/bspwm,0re5ama/bspwm,nfnty/bspwm,0re5ama/bspwm,XiKuuKy/bspwm,Stebalien/bspwm,jbalint/bspwm,netzverweigerer/bspwm,Stebalien/bspwm,0re5ama/bspwm,medisun/bspwm,baskerville/bspwm,medisun/bspwm,ikn/bspwm