Implement NVGPU_AS_IOCTL_GET_VA_REGIONS which returns a list of GPU VA
regions for different page sizes. This is required for the userspace
for safe fixed-address address space allocation.
Bug 1551752
Change-Id: I63ddde30935db2471bec498dae0caa870e89c1a5
Signed-off-by: Sami Kiminki <skiminki@nvidia.com>
Reviewed-on: http://git-master/r/590814
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>