lavf: revert commit bb99ae3ae924c942a634bec7711ec7ee11c38eb9

	Author: Michael Niedermayer <michaelni@gmx.at>
	Date:   Thu Nov 3 22:38:10 2011 +0100

	    lavf: fix null pointer dereference in rdt

	    Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This is no longer needed and causes various problems with RTSP

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
