Clarify target address for requested message/stream (#1249)

message_definitions/v1.0/common.xml

@@ -1831,11 +1831,13 @@
         <description>Set the interval between messages for a particular MAVLink message ID. This interface replaces REQUEST_DATA_STREAM.</description>
         <param index="1" label="Message ID" minValue="0" maxValue="16777215" increment="1">The MAVLink message ID</param>
         <param index="2" label="Interval" units="us" minValue="-1" increment="1">The interval between two messages. Set to -1 to disable and 0 to request default rate.</param>
+        <param index="7" label="Response Target" minValue="0" maxValue="2" increment="1">Target address of message stream (if message has target address fields). 0: Flight-stack default (recommended), 1: address of requestor, 2: broadcast.</param>
       </entry>
       <entry value="512" name="MAV_CMD_REQUEST_MESSAGE" hasLocation="false" isDestination="false">
         <description>Request the target system(s) emit a single instance of a specified message (i.e. a "one-shot" version of MAV_CMD_SET_MESSAGE_INTERVAL).</description>
         <param index="1" label="Message ID" minValue="0" maxValue="16777215" increment="1">The MAVLink message ID of the requested message.</param>
         <param index="2" label="Index ID" minValue="0" increment="1">Index id (if appropriate). The use of this parameter (if any), must be defined in the requested message.</param>
+        <param index="7" label="Response Target" minValue="0" maxValue="2" increment="1">Target address for requested message (if message has target address fields). 0: Flight-stack default, 1: address of requestor, 2: broadcast.</param>
       </entry>
       <entry value="519" name="MAV_CMD_REQUEST_PROTOCOL_VERSION" hasLocation="false" isDestination="false">
         <description>Request MAVLink protocol version compatibility</description>