MT#59962 AmOfferAnswer: no need to parse CSTA body

Not even used in `AmOfferAnswer::onReplyIn()`.

Fixes:

*** CID 583407:           (FORWARD_NULL)
/core/AmOfferAnswer.cpp: 217             in AmOfferAnswer::onReplyIn(const AmSipReply &)()
211           {
212             /* hack to handle 2xx with different tag than was in 183: accept the
213              * new SDP though we should accept the first one we received (without
214              * fork) */
215             ILOG_DLG(L_DBG, "overwriting SDP remembered within the same transaction\n");
216
>>>     CID 583407:           (FORWARD_NULL)
>>>     Passing null pointer "sdp_body" to "getPayload", which dereferences it.
217             if (sdp_remote.parse((const char*)sdp_body->getPayload())){
218               err_code = 400;
219               err_txt = "session description parsing failed";
220             } else if(sdp_remote.media.empty()){
221               err_code = 400;
222               err_txt = "no media line found in SDP message";
/core/AmOfferAnswer.cpp: 243             in AmOfferAnswer::onReplyIn(const AmSipReply &)()
237               remote_port_seen = remote.port;
238             }
239
240           } else {
241             bool is_reliable = reply.code >= 200 || key_in_list(getHeader(reply.hdrs, SIP_HDR_REQUIRE), SIP_EXT_100REL);
242             saveState();
>>>     CID 583407:           (FORWARD_NULL)
>>>     Passing null pointer "sdp_body" to "onRxSdp", which dereferences it.
243             err_code = onRxSdp(reply.cseq,reply.to_tag,is_reliable, *sdp_body,&err_txt);
244             checkStateChange();
245           }
246         }
247       }
248

Change-Id: I5298acf7ac54e3335a88cd3a18d1fea3d5436dda

core/AmOfferAnswer.cpp

@@ -198,9 +198,7 @@ int AmOfferAnswer::onReplyIn(const AmSipReply& reply)
      !reply.body.empty() )
   {
     const AmMimeBody* sdp_body = reply.body.hasContentType(SIP_APPLICATION_SDP);
-    const AmMimeBody* csta_body = reply.body.hasContentType(SIP_APPLICATION_CSTA_XML);
-
-    if (sdp_body || csta_body) {
+    if (sdp_body) {
 
       if ((reply.cseq_method == SIP_METH_INVITE) &&
           ((state == OA_Completed)