freedreno/ir3+computerator: Misc fixes + debugging

A few things I had floating around tracing an obscure rendering bug in genshin impact.. haven't found the issue there yet (game isn't traceable.. but I did narrow it down to a problem that ubo lowering triggers in one of ~400 shaders.. joy..)

Anyways, we probably want at least the first patch to fix a validate pass assert with debug builds.. and the others have been useful for debugging.