virgl: do not use inline writes for subdata

virgl: do not use inline writes for subdata

Inline writes skip transfer map/unamp at the cost of an extra copy
on the data during execbuffer.  That is generally a win for small
transfers.  But the heuristic to use inline writes based on buffer
sizes rather than transfer sizes makes little sense.  More
importantly, inline writes miss optimizations that are done for
buffer transfers.

Let's just use transfers.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-By: Gert Wollny <gert.wollny@collabora.com>