sdp: remove circular inclusion

The header file mgcp_sdp.h includes itsself.

- remove unnecessary circular inclusion

Change-Id: I816c6b922641c0b58053714244ada22a75781956
diff --git a/include/osmocom/mgcp/mgcp_sdp.h b/include/osmocom/mgcp/mgcp_sdp.h
index da23cba..240f8cf 100644
--- a/include/osmocom/mgcp/mgcp_sdp.h
+++ b/include/osmocom/mgcp/mgcp_sdp.h
@@ -21,7 +21,6 @@
  */
 
 #pragma once
-#include <osmocom/mgcp/mgcp_sdp.h>
 
 int mgcp_parse_sdp_data(const struct mgcp_endpoint *endp,
 			struct mgcp_conn_rtp *conn,