nvc0: Update counter reading shaders to new NVC0_CB_AUX_MP_INFO

Fixes: 66ca7e40 ('nvc0: add support for programmable sample locations')
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
(cherry picked from commit 01fa76b7)