linux-dmabuf: add main_device event
On multi-GPU setups, multiple devices can be used for rendering. Clients need hints about the device in use by the compositor. For instance, if they render on another GPU, then they need to make sure the memory is accessible between devices and that their buffers are not placed in hidden memory.
This commit introduces a new main_device event.
Signed-off-by: Simon Ser contact@emersion.fr
Closes: wayland#59 (moved)
Same as !8 (merged) but with only the main device.
The original MR is a lot of work and unknowns. This MR only contains the changes necessary to replace wl_drm
.