For each device a file xgmi_device_id is created.
On the first device a subdirectory named xgmi_hive_info is created,
It contains  a file named hive_id and symlinks named node 1-4 linking
to each device in the hive.

v2: Return error codes instead of '-1' and few misspellings.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>