If iptables version is < 1.4.11, try to delete the rule vs. checking if it exists. Fixes#6831.
Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jfrazelle@users.noreply.github.com> (github: jfrazelle)
Upstream-commit: f3a68ffa390fb851115c77783fa4031f1d3b2995
Component: engine