control: Require AppArmor 3

Upstream now behaves differently depending on whether AppArmor
3 or AppArmor 2 is present, and we want the newer behavior.

debian/control

@@ -13,7 +13,7 @@ Build-Depends:
  iptables [linux-any],
  kmod [linux-any],
  libacl1-dev [linux-any],
- libapparmor-dev [linux-any],
+ libapparmor-dev (>= 3.0.0) [linux-any],
  libattr1-dev [linux-any],
  libaudit-dev [linux-any],
  libblkid-dev,