[Datasource] Deprecate CRN attribute from ibm_pi_volume_snapshot(s) (IBM-Cloud#6168)

* Deprecate CRN attribute from volume snapshots

This field was mistakenly added and is not and has never been
filled out by the service broker. It currently only applies
to the instance_snapshot data source and resource.

* Update documentation

Author: ismirlia

ibm/service/power/data_source_ibm_pi_volume_snapshot.go

@@ -40,6 +40,7 @@ func DataSourceIBMPIVolumeSnapshot() *schema.Resource {
 			},
 			Attr_CRN: {
 				Computed:    true,
+				Deprecated:  "This field is deprecated.",
 				Description: "The CRN of the volume snapshot.",
 				Type:        schema.TypeString,
 			},

ibm/service/power/data_source_ibm_pi_volume_snapshots.go

@@ -41,6 +41,7 @@ func DataSourceIBMPIVolumeSnapshots() *schema.Resource {
 						},
 						Attr_CRN: {
 							Computed:    true,
+							Deprecated:  "This field is deprecated.",
 							Description: "The CRN of the volume snapshot.",
 							Type:        schema.TypeString,
 						},

website/docs/d/pi_volume_snapshot.html.markdown

@@ -47,7 +47,7 @@ You can specify the following arguments for this data source.
 In addition to all argument reference list, you can access the following attribute references after your data source is created.
 
 - `creation_date` - (String) The date and time when the volume snapshot was created.
-- `crn` - (String) The CRN for this resource.
+- `crn` - (Deprecated, String) The CRN for this resource.
 - `id` - (String) The unique identifier of the volume snapshot.
 - `name` - (String) The volume snapshot name.
 - `size` - (Float) The size of the volume snapshot, in gibibytes (GiB).

website/docs/d/pi_volume_snapshots.html.markdown

@@ -48,7 +48,7 @@ In addition to all argument reference list, you can access the following attribu
 
   Nested schema for `volume_snapshots`:
   - `creation_date` - (String) The date and time when the volume snapshot was created.
-  - `crn` - (String) The CRN of the volume snapshot.
+  - `crn` - (Deprecated, String) The CRN of the volume snapshot.
   - `id` - (String) The volume snapshot UUID.
   - `name` - (String) The volume snapshot name.
   - `size` - (Float) The size of the volume snapshot, in gibibytes (GiB).