The render extension uses many matrix operations internally, this change
exposes those functions to other parts of the server, drivers and
extensions. The change is motivated by the 'transform' additions to the
RandR extension but will likely be useful elsewhere.
Get rid of almost all uses of these definitions. They're still defined for
delinquent out-of-tree drivers, and also for the Mesa build. As well as
for miinitext.c. But largely gone.
