sh: no need to reset handler if SA_ONESHOT

get_signal_to_deliver() already resets the signal handler if SA_ONESHOT is
set in ka->sa.sa_flags, there's no need to do it again in handle_signal().
 Furthermore, because we were modifying ka->sa.sa_handler (which is a copy
of sighand->action[]) instead of sighand->action[] the original code had
no effect on signal delivery.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>