drm/amdkfd: CRIU prepare for svm resume

During CRIU restore phase, the VMAs for the virtual address ranges are
not at their final location yet so in this stage, only cache the data
required to successfully resume the svm ranges during an imminent CRIU
resume phase.

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>