drm/msm/a6xx: Fix missing ARRAY_SIZE() check

Fixes: f6d62d09 ("drm/msm/a6xx: add support for Adreno 660 GPU")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220305173405.914989-1-robdclark@gmail.com