strparser: Use delayed work instead of timer for msg timeout

Sock lock may be taken in the message timer function which is a
problem since timers run in BH. Instead of timers use delayed_work.

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Fixes: bbb03029

 ("strparser: Generalize strparser")
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>