FIB: remove assert from adj src
FIB: remove assert from adj src

this is the case when the ADJ fib is in the non-forwarding trie

Change-Id: I7bcda475b3b1e142d16363147dba3a1e2c5a07f9
Signed-off-by: Neale Ranns <b9c0e9ef0223633bc2f318425f615cf5840a0be7@cisco.com>

FDio/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp