bpf: Remove unnecessary sk stack initialization
bpf: Remove unnecessary sk stack initialization

These lines were initializing 'sk' on the stack unnecessarily, as they
will be unconditionally set just a few lines below. Fix it.

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

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