prog_test: Fix build breakage
prog_test: Fix build breakage

Commit 845a062c0fdf ("monitor: Remove package-level link monitor") broke
this test by refactoring the monitor function signature. Fix it by
overhauling this code to match the new usage model.

Reported-by: Timo Beckers <98c2d5a1e48c998bd9ba9dbc53d6857beae1c9bd@isovalent.com>
Signed-off-by: Joe Stringer <16a9a54ddf4259952e3c118c763138e83693d7fd@cilium.io>

michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium,cilium/cilium