[seL4] Too large messages

There've been a few messages stuck in the queue recently because they're too large for the list.

Please remember when sending to the Devel@sel4.systems list -- trim what you're replying to, to just the relevant bits -- reply in-line (no top-posting) -- send only plain text (not screen shots or HTML). Serial port output can be pasted in-line.

This will maximise your chance of getting email through on first attempt.