libav - security update

Don A. Baley discovered an integer overflow in the lzo compression
handler which could result in the execution of arbitrary code.

For the stable distribution (wheezy), this problem has been fixed in
version 6:0.8.13-1.

For the testing distribution (jessie), this problem has been fixed in
version 6:10.2-1.

For the unstable distribution (sid), this problem has been fixed in
version 6:10.2-1.

We recommend that you upgrade your libav packages.