- Rename ata-timings.h to timings.h. Same arguments as for agp.

 - Always include hdparm.h just before ide.h. Include them last where
   used. This is preparing to split out the IDE register declarations
   out of this file, since many other files in the kernel include it,
   which don't have anything to do with IDE.

 - Don't use the "IDE special" data type "byte". Just use the u8 data
   type for consistency with the rest of the kernel where applicable.