configure: remove support for internal libdvd*.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@37317 b3059339-0415-0410-9bf9-f77b7e298cf2
vd_ffmpeg: Fix compilation without VDPAU.

Based on patch by Stephen Sheldon [sfsheldo gmail].

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@37318 b3059339-0415-0410-9bf9-f77b7e298cf2
Remove now unused libdvdread/libdvdnav svn:externals.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@37319 b3059339-0415-0410-9bf9-f77b7e298cf2
Remove remaining parts of internal libdvdnav, libdvdread and libdvdcss.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@37320 b3059339-0415-0410-9bf9-f77b7e298cf2