endpoint: Refactor CFG_L4_*GRESS accumulation
endpoint: Refactor CFG_L4_*GRESS accumulation

Refactor the way that we generate CFG_L4_INGRESS and CFG_L4_EGRESS. An
upcoming commit will split this into two, to differentiate l3-dependent
L4 vs. L3-independent L4.

Signed-off-by: Joe Stringer <16a9a54ddf4259952e3c118c763138e83693d7fd@covalent.io>

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