Consider re-enabling expression tree simplification in the AppArmor parser
Originally created by @intrigeri on #15760 (Redmine)
AppArmor 2.13-7 will “parser.conf: turn off expression tree simplification, that makes performance much worse in some cases”, which I think will introduce a boot time regression for Tails. We should measure that and if indeed it is a regression, revert this `/etc/apparmor/parser.conf` patch in Tails.