freedreno, tu: Register changes, one more pvtmem fix for a650
Not sure how this worked for me the first time, but we need to set SP_XS_PVT_MEM_HW_STACK_OFFSET
to get pvtmem working on a650. However to avoid hardcoding the shift in the register I needed to make some other changes to the register infrastructure which unfortunately caused a lot of other churn in freedreno.