Update dvdread in dvdnav

ASSERT dsi->dsi_gi.zero1 == 0 failure during DVD reading

Movie stops in the middle of last chapter. Example: Artificial Eye DVD "Ivan's Childhood".

Error messages:

• "dsi->dsi_gi.zero1 == 0" (from libdvdread) and "i_pack_len >= 1024" (from vlc's dvdread access module) or:
• "Expected NAV packet but none found." (when using libdvdnav only)

My solution: In modules/access/dvdread.c, line 1151, replace "p_sys->i_next_vobu = p_sys->i_cur_block + ( p_sys->dsi_pack.vobu_sri.next_vobu & 0x7fffffff );" by "p_sys->i_next_vobu = p_sys->i_cur_block + p_sys->i_pack_len + 1;"