tipc: enable creating a "preliminary" node
When user sets RX key for a peer not existing on the own node, a new node entry is needed to which the RX key will be attached. However, since the peer node address (& capabilities) is unknown at that moment, only the node-ID is provided, this commit allows the creation of a node with only the data that we call as “preliminary”. A preliminary node is not the object of the “tipc_node_find()” but the “tipc_node_find_by_id()”. Once the first message i.e. LINK_CONFIG comes from that peer, and is successfully decrypted by the own node, the actual peer node data will be properly updated and the node will function as usual. In addition, the node timer always starts when a node object is created so if a preliminary node is not used, it will be cleaned up. The later encryption functions will also use the node timer and be able to create a preliminary node automatically when needed. Acked-by:Ying Xue <ying.xue@windreiver.com> Acked-by: