clarify that sdpFmtpLine may not be there (#780)

* clarify that sdpFmtpLine may not be there

fixes #779

* remove JSEP alias

* Update webrtc-stats.html

Co-authored-by: Philipp Hancke <fippo@goodadvice.pages.de>

---------

Co-authored-by: Harald Alvestrand <hta+github@alvestrand.no>

webrtc-stats.html

@@ -875,8 +875,11 @@ <h2>
               </dt>
               <dd>
                 <p>
-                  The a=fmtp line in the SDP corresponding to the codec, i.e., after the colon
-                  following the PT. This defined by [[!JSEP]] in Section 5.7.
+                  The "format specific parameters" field from the
+                  <code class="sdp">a=fmtp</code> line in the SDP
+                  corresponding to the codec, if one [= map/exist =]s,
+                  as defined by
+                  [[!RFC8829]] (<a href="https://www.rfc-editor.org/rfc/rfc8829#section-5.8">section 5.8</a>).
                 </p>
               </dd>
             </dl>

webrtc-stats.js

@@ -99,9 +99,6 @@ var respecConfig = {
             status:   "Internet Draft",
             publisher:  "IETF"
         },
-        "JSEP": {
-		"aliasOf": "RFC8829"
-        }
       },
   postProcess: [
     function generateStatsHierarchy(config, doc) {