Update package deps to remove LXC and move aufs-tools to be in "Recommends" instead of strict Depends

Docker-DCO-1.1-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)

hack/make/ubuntu

@@ -112,9 +112,8 @@ EOF
 		    --after-remove /tmp/postrm \
 		    --architecture "$PACKAGE_ARCHITECTURE" \
 		    --prefix / \
-		    --depends lxc \
-		    --depends aufs-tools \
 		    --depends iptables \
+		    --deb-recommends aufs-tools \
 		    --deb-recommends ca-certificates \
 		    --deb-recommends xz-utils \
 		    --description "$PACKAGE_DESCRIPTION" \