isisd: exit if daemonizing fails

The other daemons in Quagga exit with an error if they cannot fork.
Change isisd to behave consistently.

Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Tested-by: NetDEF CI System <cisystem@netdef.org>
Acked-by: Donald Sharp <sharpd@cumulusnetworks.com>
1 file changed