Block suspend for 60 seconds if dsme makes abnormal exit

If dsme makes abnormal exit, it will acquire a wakelock that will
automatically cancel after 60 seconds. This makes sure the device is
not suspended while systemd is either restarting the dsme service or
rebooting the device.

Blocking suspend also makes sure hw watchdog does not get fed by random
suspend-resume cycles and there will be watchdog reboot if systemd does
not manage to restart dsme / shutdown the device in time.

Additionally watchdogs are fed one more time if dsme is about to exit
due to terminal signal. This makes sure a full watchdog timeout period
is available for core dumping and dsme process restarting.

Signed-off-by: Simo Piiroinen <simo.piiroinen@jollamobile.com>