review: remove redundant --rdd6 description in rdd6_xml_creator

meta/rdd6_xml_creator/README.md

@@ -10,8 +10,6 @@ Open `index.html` in a web browser and fill-in the RDD 6 metadata. Select "Save
 
 The exported XML file can be passed to the `bmxtranswrap` tool using the `--rdd6 <file>` commandline option.
 
-The RDD 6 XML can be extracted from an MXF file using `mxf2raw` and the `--rdd6 <frames> <file>` option.
-
-> Set the `<frames>` argument to a single MXF frame (e.g. `10`) or sequence of MXF frames (e.g. `0-10`) to extract the RDD 6 metadata. The RDD 6 metadata is the same in each frame except for the program description which is spread across multiple frames. Each frame has 1 character of the description text, a description start byte (0x02) or a description end byte (0x03).
+The RDD 6 XML can be extracted from an MXF file using `mxf2raw` and the `--rdd6 <frames> <file>` option. See the `mxf2raw` usage message for more details and what `<frames>` is for.
 
 The XML Schema for the RDD 6 XML can be found in [../rdd6/rdd6.xsd](../rdd6/rdd6.xsd).