fixup! BOLT 7: add gossip address descriptor type DNS hostname

Author: m-schmoock

07-routing-gossip.md

@@ -314,7 +314,7 @@ The origin node:
   - SHOULD set `flen` to the minimum length required to hold the `features`
   bits it sets.
   - SHOULD not announce a Tor v2 onion service.
-  - SHOULD NOT announce more than one `type 5` DNS hostname.
+  - MUST NOT announce more than one `type 5` DNS hostname.
 
 The receiving node:
   - if `node_id` is NOT a valid compressed public key:
@@ -349,6 +349,9 @@ any future fields appended to the end):
   - MAY use `rgb_color` AND `alias` to reference nodes in interfaces.
     - SHOULD insinuate their self-signed origins.
   - SHOULD ignore Tor v2 onion services.
+  - if more than one `type 5` address is announced:
+    - SHOULD ignore the additional data.
+    - MUST not forward the `node_announcement`.
 
 ### Rationale