eigrpd: Fix non-installation of routes into zebra

eigrpd: Fix non-installation of routes into zebra

EIGRP was not installing routes it learned from it's
neighbors into the rib.

This is probably a hack, but zebra now knows about the
routes.

robot.cumulusnetworks.com# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP,
       O - OSPF, I - IS-IS, B - BGP, P - PIM, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct,
       > - selected route, * - FIB route

K>* 0.0.0.0/0 via 10.0.2.2, enp0s3
C>* 10.0.2.0/24 is directly connected, enp0s3
E   192.168.2.0/24 [0/0] via 127.0.0.1, enp0s10 inactive
C>* 192.168.2.0/24 is directly connected, enp0s10
E>* 192.168.3.4/32 [0/0] via 192.168.2.144, enp0s10
E>* 192.168.4.5/32 [0/0] via 192.168.2.144, enp0s10
E>* 192.168.4.6/32 [0/0] via 192.168.2.144, enp0s10
C>* 192.168.22.11/32 is directly connected, lo
robot.cumulusnetworks.com# show ip route 192.168.4.5
Routing entry for 192.168.4.5/32
  Known via "eigrp", distance 0, metric 0, best
  * 192.168.2.144, via enp0s10

robot.cumulusnetworks.com#

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>