zink+gallium/u_transfer_helper: unify full api and (de)interleave api
Zink uses a subset of the u_transfer_helper
API that only supports (de)interleaving z/stencil buffers. But doing this currently makes it impossible to use the other features of u_transfer_helper
without duplicating their logic. This unifies these code-paths into one, so we can start using other helpers in the future.
I'm not terribly happy with the U_TRANSFER_HELPER_*
flag names, especially U_TRANSFER_HELPER_INTERLEAVE_IN_PLACE
. But I can't come up with better ones, it seems... Better suggestions are welcome!