BOLT 4: modernize tlv labels so extract-formats.py can find them.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

04-onion-routing.md

@@ -377,7 +377,7 @@ is no legacy format, thus a `bigsize` of 0 means no payload.
 An intermediate node expects an `enctlv` which it can decrypt using
 the `blinding` which it is handed along with the onion message.
 
-1. tlvs: `onionmsg_payload`
+1. `tlv_stream`: `onionmsg_payload`
 2. types:
     1. type: 8 (`reply_path`)
     2. data:
@@ -388,7 +388,7 @@ the `blinding` which it is handed along with the onion message.
     2. data:
         * [`...*byte`:`enctlv`]
 
-1. tlvs: `encmsg_tlvs`
+1. `tlv_stream`: `encmsg_tlvs`
 2. types:
     1. type: 1 (`padding`)
     2. data: