This ensures that the dvd_reader_t struct is initialized (e.g. the css_state
field is currently undefined if 'have_css' is false).

The patch is part of a bigger MythTV-specific change by Chris Pinkham:
https://github.com/MythTV/mythtv/commit/3af3489Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>