zink: add extra synchronization for buffer descriptor binds
"most" times it isn't necessary to insert any pipeline barriers when binding descriptors, as GL requires explicit barrier usage which comes through a different codepath
the exception here is when the following scenario occurs:
- have buffer A
- buffer_subdata is called on A
- discard path is taken || A is not host-visible
- stream uploader is used for host write
- CmdCopyBuffer is used to copy the data back to A buffer A now has a pending TRANSFER write that must complete before the buffer is used in a shader, so synchronization is required any time TRANSFER usage is detected in a bind
there's also going to be more exceptions going forward as more internal usage is added, so just remove the whole fake-barrier mechanism since it'll become more problematic going forward
Cc: 21.3 mesa-stable