These drivers 'inherited' the license of the old agpgart code, which was
licensed as 'and additional rights' even though those rights were never
publically documented anywhere to my knowledge.
This was a hangover from the days when agpgart maintainence was done primarily
in the X tree, where GPL code cannot live without 'additional rights'.

These days, agpgart maintainence happens in the kernel tree, so these
'additional rights' mean nothing.  Remove them from some drivers.
(More to follow).
Signed-off-by: Dave Jones <davej@redhat.com>