freedreno, turnip: a605,608,610,612 bringup

Supersedes !20966 (closed)

a608 is same as a610 judging from dumps obtained via libwrapfake.

a610/a608 have the following things different that are the same on all other gens:

• 16 VSC pipes, while other models have 32;
• A difference in one flag in HLSQ_CONTROL_1;
• A difference in depth and color ccu cache sizes;
• ??? In dumps I saw a write into 0x8e09 at command buffer setup, this reg is considered invalid in our definition.