The port agnostic allocator helpers in mmal leak memory (see
https://github.com/raspberrypi/firmware/issues/310). As there is no benefit
using them instead of the default allocator in our case anyway, switch to the
default allocator, which avoids memory leakage on pool destruction.
Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>