ratelimit: add comment warning people off printk_ratelimit()

printk_ratelimit() was a bad idea - we don't want subsytem A causing
ratelimiting of subsystem B's messages.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed