vkr: support VK_KHR_copy_commands2
Adds as a supported extension and implements dispatch handlers for new functions.
Results of deqp-vk -n dEQP-VK.api.copy_and_blit.copy_commands2.*:
| Native | Venus | |
|---|---|---|
| Passing | 3799 | 3799 |
| Failing | 0 | 0 |
| Not Supported | 5832 | 5832 |
mesa: mesa/mesa!17226 (merged)
Signed-off-by: Ryan Neph ryanneph@google.com
/cc @zzyiwei @chadversary