Map restart signals from event loop to SIGTERM during exit-notification wait

Map restart signals from event loop to SIGTERM during exit-notification wait

Commit 63b3e000c9.. fixed SIGTERM getting lost during exit notification
by ignoring any restart signals triggered during this interval. However,
as reported in Trac 777, this could result in repeated triggering of
restart signals when the event loop cannot continue without restart due
to IO errors or timeout.

Avoid by converting soft SIGUSR1 and SIGHUP signals received during
exit-notify wait period to SIGTERM.

cherry-picked from commit f25a0217e35f53c3110ebb226e1d1f3528152cb5
with (c->sig->source == SIG_SOURCE_HARD) changed to c->sig->hard

Trac: #777

Signed-off-by: Selva Nair <selva.nair@gmail.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1480470535-6287-1-git-send-email-selva.nair@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg13310.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>