policy: DNS L7 visibility policy uses global wildcard selector
policy: DNS L7 visibility policy uses global wildcard selector

Visibility policies are generated specifically for the DNS proxy as
allow-all policies. The L3 selector is also setup to be a select-all,
but would crash when .Selects was invoked on it. The selector is now
safer to use, particularly as it self-identities as a wildcard selector
and skips the panicking line.

Signed-off-by: Ray Bejjani <7f525154e857f3d57a641a83dddc584f42addc6a@isovalent.com>

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