This patch adds just enough TImode vector support to use them for moving 
data about. This is primarily for the use of divmodv64di4, which will 
use TImode to return a pair of DImode values.

The TImode vectors have no other operators defined, and there are no 
hardware instructions to support this mode, beyond load and store.

Committed to mainline, and OG13 will follow shortly.

Andrew