radeon: update radeon_drm.h to kernel last API additions v2

v2: sync with radeon-next tree for 3.10

http://cgit.freedesktop.org/~agd5f/linux/log/?h=drm-next-3.10-wip



Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>