winsys/amdgpu: Add R600_DEBUG flag to reserve VMID per ctx.

Fixes reverted patch f03b7c9 by doing VMID reservation per
process and not per context.
Also updates required amdgpu libdrm version since the change
involved interface updates in amdgpu libdrm.

Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Signed-off-by: Marek Olšák <marek.olsak@amd.com>
6 files changed