fix various errors and warnings with xorg-server 1.20:

- no Error() in scope
- more wakeup/blockhandler ABI changes
- more notify fd API changes
- more xf86CursorResetCursor changes
- lots of char* -> const char*
- fix ati kms config.h now HAVE_XF86_CURSOR_RESET_CURSOR is available
- another xf86GetOS() is removed fix
- OsBlockSIGIO() etc, -> old, but still around API until properly converted
- don't free const char * data owned by some other system

initial import of xf86-video-ati-7.8.0

initial import of xf86-video-ati-6.14.6

initial import of xf86-video-ati-7.7.0

initial import of xf86-video-ati 7.5.0 sources, into a new subdir as
this only has a chance of working on systems with KMS -- -7 on x86
only, so we need to keep the 6.x around for everyone else.