pkg/endpoint: access policy enforcement configuration directly in computeDesiredL3PolicyMapEntries
pkg/endpoint: access policy enforcement configuration directly in computeDesiredL3PolicyMapEntries

Instead of calling `owner.EnableEndpointPolicyEnforcement` when generating the
desired L3 PolicyMap entries, we can simply just check the configuration of the
endpoint directly, which should encode whether the endpoint enforces policy at
ingress or egress. This removes the need to iterate over all rules and all
identities in the policy repository again.

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

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