freedreno/regs: add extra bits for UBWC array pitch

This is not completely tested, but matches the max array pitch allowed by
A6XX_TEX_CONST_9_FLAG_BUFFER_ARRAY_PITCH.

Note this still doesn't allow all image sizes, but it allows 16384x16384
cpp=4 images to work.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5678>