ipam: Don't recalculate if resource is not attached yet
ipam: Don't recalculate if resource is not attached yet

There is no point in attempting recalculation of required addresses
unless the resource has been attached.

Signed-off-by: Thomas Graf <5f50a84c1fa3bcff146405017f36aec1a10a9e38@cilium.io>

cilium-team/cilium,tgraf/cilium,tgraf/cilium,tklauser/cilium,michi-covalent/cilium,cilium/cilium,tgraf/cilium,tklauser/cilium,tklauser/cilium,tgraf/cilium,michi-covalent/cilium,tgraf/cilium,cilium-team/cilium,michi-covalent/cilium,cilium/cilium,tklauser/cilium,cilium/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,tklauser/cilium,tgraf/cilium,michi-covalent/cilium