V4L/DVB (11733): increase MPEG encoder timout

If video has a lot of changes in frame, MPEG encoder need more time for
coding process. Add new bigger timeout for encoder.

This is patch from our customer. I checked this.

Signed-off-by: Alexey Osipov <lion-simba@pridelands.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>