Since wildcards that need recursion consume kernel stack memory (or might
cause CPU stall warning problem), we cannot allow infinite recursion.
Since TOMOYO 1.8 survived with 20 recursions limit for 5 years, nobody
would complain if applying this limit to TOMOYO 2.6.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>