bgpd: fix vni table output broken by 8304dabfab906

bgpd: fix vni table output broken by 8304dabfab906

Fix vni table output broken by 8304dabfab9063fe5720e8e714476ed2e9127540

The "Imported from" output was not getting delimitted by a newline
after the mentioned commit. This fixes that and retains the output
wanted by the original change.

Before:

'''
  Route [2]:[0]:[48]:[b6:3a:cc:d5:a1:cd]:[128]:[fe80::b43a:ccff:fed5:a1cd] VNI 30/10  Imported from 2.2.2.2:4:[2]:[0]:[48]:[b6:3a:cc:d5:a1:cd]:[128]:[fe80::b43a:ccff:fed5:a1cd], VNI 30/10

  2
    2.2.2.2(alfred) from alfred(veth1) (2.2.2.2)
      Origin IGP, valid, external, bestpath-from-AS 2, best (First path received)
      Extended Community: RT:2:30 ET:8
      Last update: Fri Oct  7 16:04:59 2022
'''

After:

'''
  Route [2]:[0]:[48]:[b2:cf:96:70:4f:b6]:[128]:[fe80::b0cf:96ff:fe70:4fb6] VNI 30/10
  Imported from 2.2.2.2:4:[2]:[0]:[48]:[b2:cf:96:70:4f:b6]:[128]:[fe80::b0cf:96ff:fe70:4fb6], VNI 30/10
  2
    2.2.2.2(alfred) from alfred(veth1) (2.2.2.2)
      Origin IGP, valid, external, bestpath-from-AS 2, best (First path received)
      Extended Community: RT:2:30 ET:8
      Last update: Fri Oct  7 17:02:28 2022
'''

Signed-off-by: Stephen Worley <sworley@nvidia.com>