proxy: Only mark the port as allocated if not already configured.
proxy: Only mark the port as allocated if not already configured.

Check if proxy port has already been configured in reservePort(). This
is a cleanup only, should not change existing behavior.

Signed-off-by: Jarno Rajahalme <0f1ab0ac7dffd9db21aa539af2fd4bb04abc3ad4@covalent.io>

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