drm/amdkfd: bind cpu and hiveless gpu to a hive if xgmi connected

If a CPU and GPU are xGMI connected but the GPU is hiveless with
respect to other GPUs, create a new CPU-GPU hive using the GPU's PCI
device location ID as the new hive ID to maintain fine grain memory
access usage.

Signed-off-by: Jonathan Kim <jonathan.kim@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>