isisd: Add new adjacency to LSP neighbor list

isisd: Add new adjacency to LSP neighbor list

isis_pdu.c :
New adjacency did not always get added to LSP neighbor list.

The adjacencies that were created once minimum time allowed before LSP
retransmission had surpassed, instantly got their LSP regenerated, but
the adjacency circuit type was not set to IIH PDU circuit type before
the LSP was regenerated , hence didn't pass the check for adjacency
circuit type in lsp_build(), and the adjacency was not added to neighbor list.

When a new adjacency is up, to build LSP with neighbor entry corresponding
to the adjacency, set adjacency circuit type to circuit type from hello PDU
header before new LSP is regenerated/built. This will result in the new
adjacency entry getting added to the LSP neighbor list TLV.

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
(cherry picked from commit 06cc655c0345d610eb946bd41968caa03dc118ed)