cilium/cmd: refactor parseTrafficString
cilium/cmd: refactor parseTrafficString

Use a switch statement instead of if-else chain.

Signed-off by: Ian Vernon <ian@cilium.io>

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