Okay. NOT redundancy, just to add capacity.
In that case, you don't need a VRRP.
For the APs that will be on the primary controller, the ap-group has an ap system profile, which has an lms-ip which should point to the controller your want the APs to be on. In summary:
ap-group
ap system profile
lms-ip
At minimum, you will have two ap-groups. One ap group will have an AP system profile which will have an LMS-ip which will point to the first controller. The second ap group will have an AP system profile which will have an LMS-ip which points to the second controller. You will just provision APs to the ap-group which has the LMS-IP of the controller that you want them to be on.