sws_utils: remove custom GBRP conversion

We needed this because the OSD rendering path used GBRP for RGB
rendering, and not all swscale versions supported this conversion. But
recently we've dropped support for very old ffmpeg/libav versions, so
this isn't needed anymore.
joystick: Fix incorrect pointer offset code.

I have some doubts that short reads are even allowed/
possible for /dev/js*, does someone know for sure?

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@37132 b3059339-0415-0410-9bf9-f77b7e298cf2
terminal-unix: reject overlong termcap strings

Our own tables have size for only 8 chars, so these sequences must be
rejected. It seems strings of length 8 are still ok, because the code
uses memcmp and not strcmp, so still allow these.

Based on mplayer-svn commit r37129.