net/tipc: fix all function Return: notation

Fix Return: kernel-doc notation in all net/tipc/ source files.
Also keep ReST list notation intact for output formatting.
Fix a few typos in comments.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/net/tipc/discover.c b/net/tipc/discover.c
index 40c1168..5380f60 100644
--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -342,7 +342,7 @@ static void tipc_disc_timeout(struct timer_list *t)
  * @dest: destination address for request messages
  * @skb: pointer to created frame
  *
- * Returns 0 if successful, otherwise -errno.
+ * Return: 0 if successful, otherwise -errno.
  */
 int tipc_disc_create(struct net *net, struct tipc_bearer *b,
 		     struct tipc_media_addr *dest, struct sk_buff **skb)