The only user of send_sigio_to_task() already holds tasklist_lock, so it is
better not to send the signal via send_group_sig_info() (which takes
tasklist recursively) but use group_send_sig_info().

The same change in send_sigurg()->send_sigurg_to_task().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>