drm/i915/adlp: Require always a power-of-two sized CCS surface stride

At the moment CCS FB strides must be power-of-two sized, but a follow-up
change will add support remapping these FBs, allowing the FB passed in
by userspace to have a non-POT sized stride. For these remapped FBs we
can only remap the main surface, not the CCS surface. This means that
userspace has to always generate the CCS surface aligning to the POT
stride padded main surface (by setting up the CCS AUX pagetables
accordingly). Adjust the CCS surface stride check to enforce this.

No functional change.

v2:
- Fix the gen12_ccs_aux_stride() is not static sparse warning.

Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210906182715.3915100-3-imre.deak@intel.com