Decode file path in sout-rtp-sdp

(cherry picked from commit 12cf82c8)

modules/stream_out/rtp.c

@@ -668,6 +668,7 @@ static void SDPHandleUrl( sout_stream_t *p_stream, const char *psz_url )
         if( psz_url[0] == '/' && psz_url[1] == '/' )
             psz_url += 2;
         p_sys->psz_sdp_file = strdup( psz_url );
+        decode_URI( p_sys->psz_sdp_file ); /* FIXME? */
         FileSetup( p_stream );
     }
     else